compilers/pirc: * fixed macro expansion rule * some minor refactoring * fixed some documentation.
compilers/pirc:
* fixed macro expansion rule
* some minor refactoring
* fixed some documentation.

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@17766 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

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