Adding methods to check the operation of bitvectors (isConcat,isExtend...). The corresponding methods for simple operations already exist (isAdd,isAnd,isEqual,isLess...).

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@13473 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c