added blocks method
internalized linear coeffient extraction
small stuff
resolved spurious conflict
added retailers dataset
group variables can be defined with regexps
stacked bar chart for analysing confrontations
untracking my ad-hoc testing script
bugfix in barplot
Errors can now be raised; options can be set (issue #3)
bugfix in barplot (again)
added key parameter to confront methods for validator and indicator. Closes issue #7
fixed bug in blocks
added summary method for expressionset objects
better call matching in confrontation
Added include statement option, resolving issue #1
added preprocessing options for permanent variables. Sovels issue #2, #11, #12
some documentation improvements
removed 'source' option
tests