Changed script generator to allow a path for config files and templates (MKEXP_PATH); directories are separated by colon.

* Added optional template for namelists (namcouple)
* Added info line for generated files (mkexp_input variable)
* Added model directory to 'getexp' output

* Added namelist defaults for afterburner select lists
* Change mkexp to allow variables in top-level namelist definition

* Merged r3149: Fixed cleaning of packaged CDI library. from trunk/echam-dev
* Added removal of config.inc, stamp files
* Added mkexp sub directory to distclean chain

* Changed job extension to also inherit job settings (used to inherit script only)
* Changed job extension to allow namelist overwriting per job
* Namelist overwriting requires copying of the configuration data; this should be revisited

Changed script generation to allow suppressing of default jobs by 'remove' keyword in 'jobs' section

Changed script generation to allow easier namelist setup (helper variables in namelists, evaluation of lists as strings; see EaSyMS13 IssueID #3621)

* Changed to support list valued expressions
* Changed to support expressions in lists

* Removed unused scripts
* Fixed module loading
* Anonymized default settings

* Renamed 'queue_settings' to 'environment'
* Changed to allow overriding environment by command line settings
* Added file system layout for blizzard and thunder to environment
* Fixed partition name for thunder

* Added evaluation of expressions (eval(...))
* Re-wrote splitting of date strings (now uses split_date(...))

* Added missing version keywords in scripts and modules
* Updated some of the header comments

* Added handling of experiment description
** Initial comment is parsed if no EXP_DESCRIPTION is set
** Description is written to script directory as README file
* Added setting of top-level settings from command line

* Updated Makefile

* Changed directories to be fully configurable by default config
* Added tools for diff, printing, removal of experiment/script data

* Changed directories to be fully configurable by default config
* Added tools for diff, printing, removal of experiment/script data

* Added error handling for interpolation of configuration values
* Changed command line error to use logging interface
* Reduced verbosity of template defaulting

* Change misnamed EXPNAME keyword to EXP_TYPE

* Updated and extended example configurations

* Renamed default files from 'exp.*' to 'DEFAULT.*'

* Updated default template according to r2975, r2976