Merge pull request #24 from ckaestne/canalysisoptions

ICAnalysisOptions and InterCFG
simplify the CAnalysis interface
minor cleanup, remove dead private function
simplify frontend by removing casts

an AST should always present a translation unit. introduced one cast to avoid many others
remove multiple typechecks in canalysis
merge -A and -S for static analysis: command line parameters
merging master
add default options to cinteranalysisfrontend to fix compile error