Add 'make docs' for convenience
IRC_DOXYGEN macro as a workaround to get rid of the remaining warnings
libcommuni.pro: update OTHER_FILES
Silence the annoying IsUTF8Text() compilation warning

../3rdparty/mozilla/rdf_utils.c:93:18: warning:
    comparison of constant 237 with expression of type 'const char' is
    always false [-Wtautological-constant-out-of-range-compare]