Remove duplicate class FunctionCallCollector

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@13510 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c
Restructure CFA package: create subpackage postprocessing
and move all post-processings there.

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@13511 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c