(Autoconf) Add Valgrind package support, --with-valgrind

Add new $ROSE/configure options to speicfy Valgrind support:

    --with-valgrind
    --with-valgrind-bin
    --with-valgrind-lib
    --with-valgrind-include

Currently, Valgrind is used in two ways:

    1. Enable uninitializedFields_tests (EDG test)
    2. Use during some $ROSE/tests
(Build System) Use AM_V_GEN to reduce output spew in custom targets
fix make check in testCpreprocessorOption
(Autoconf) Remove AC_SUBST(VALGRIND) since it enables failing Valgrind tests
Merge remote-tracking branch 'origin/master' into HEAD