* "01_files" contained a single "source" transformation which listed the contents of the "00_content" level
** this was unnecessary as the base "list" transformation already lists the contents of all levels
* added new "expression" mode to datasource meta tag processing in the task processing transformation
** this expression modes allows for the evaluation of arbitrary XPath statements
*** e.g. a query to the results of "list.xsl"
* modified base transformation datasource structures to include the level and meta tree
* modified all existing content transformations to query the level-tree instead of the deprecated "source.xml"
** i.e. XPath statements
** the main change is that directories are available as "directory" nodes instead of nodes named by the directory name
* these changes where implemented to simplify the architecture and to increase flexibility

* transformations contain one or more "datasource" meta nodes
** these nodes define the required datasources
** up until now it was required to define the whole path to the file to be loaded
* the implementation of directory linkage in b942f8e removed the underlying need for providing the source / target prefix
** this commit now updates the generation transformations to match this change
*** this simplifies the datasource definition process for the end-user
*** additionally it makes the target / source directories easier to maintain
* changed cleanage task implementation to remove the whole directory and recreate it from scratch
** otherwise directory linkage and in turn the whole generation failed when the target directory did not exist in the first place
* removed task reordering in the process transformation
** tasks are now processed exactly as they were scheduled
** this was changed so that e.g. the "00_content" directory is linked before the first datasource is required

* e.g. removing the target directory before each regeneration and symlinking CSS files
** this will be extended to include ressource directories and so on
* renamed "formatter.xsl" stylesheet to "helper.xsl" as it now includes various helper templates
* finally checked the main CSS into the VCS

* expanded "02_data/pages.xsl" transformation to include pages in subfolders
* "03_meta/categories.xsl" transformation generates a categorized view of all pages simmilar to the one provided for tags by "03_meta/tags.xsl"
* "99_result/category/category.xsl" transformation generates category overview pages
* added basic project related pages inside the "projects" category

* implemented language selection for automatic syntax highlighting
** language selection requires the language to be used to be passed as a class of the code element
** kramdown enables easy definition of this class attribute
* kramdown offers more functionality such as table and class attribute support
* updated all articles accordingly

* directly pass the executable including its arguments
** the "highlight.sh" proxy script is no longer required
* this was made possible by a recent commit to InputXSLT

* replaced "pre" node returned by the hightlighting script with an unstyled one
* "pre" style is now declared in css

* disable indentation in both the page and datasource master stylesheets
** indentation was interfering with correct output of formatted code
* simplified call to formatter helper template

* i.e. inline code is automatically highlighted using an external syntax highligher

* the output node is defined in both the master and datasource transformation
** i.e. they do not have to be defined in transformations making use of one of these transformations

* this is needed for the implementation of a article datasource grouped by year
** this in turn is needed for the archive page template
* modified tags meta transformation and article result transformation accordingly

* xalan and/or InputXSLT namespace should only be included when they are actually required

* contains tags and their articles but no further article data
* the unaugmented tags datasource is merged with article data on the metadata level

* this was done to simplifiy support data queries while resolving the main datasource

* articles are tagged by symlinking them to the appropriate "tag" in the "tags" directory
* tags are resolved by the article datasource transformation
* added tags for the example articles

* articles contain the handle and date in their file name
** i.e. it is split using XPath string functions
** usage of the ISO date format provides automatic ordering
* added some articles from my blog as example data

* 'h1' node is used as title and any other node as content
* modified result page transformation accordingly

* "source" directory contains layers as subdirectories
** ordered by their name
** e.g. layer 0 is "00_content" and contains the content alongside some metadata
* transformations contained within the "source" layers are processed sequentally
* transformations define their requirements in a "meta" variable
** the "meta" variable is interpreted by the core transformation "generate.xsl"
* requirements are currently datasources and target information
** every transformation may have one datasource of type "main"
*** this data source offers e.g. the option to iterate over it
** every transformation may have a arbitrary number of "support" datasources
*** e.g. "meta" is a support datasource
** the target node may provide a fixed target path or a Xpath to be evaluated
* the result of each transformation is written to the appropriate layer of the "result" directory
* this approach to XSLT based static site generation should be quite flexible and offer good expandability
** e.g. adding new datasource options and types