- use $(CC) instead of gcc when building testexpr2

- modify ast_expr2.fl and ast_expr2.y to not try to register the file version
  in a STANDALONE build
- add config.status as a dependency on testexpr2 to ensure configure is
  executed before building it
- add include/asterisk/buildopts.h as a dependency for testexpr2 as well
- add -Iinclude to the gcc commands for building the testexpr2 objects so that
  it can find the local asterisk headers


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@34980 65c4cc65-6c06-0410-ace0-fbb531ad65f3