Add --help and --version options.


git-svn-id: svn://svn.tartarus.org/sgt@10265 cda61777-01e9-0310-a592-d414129be87e
Remove the version number from the Tweak status bar.

It's about to get longer in a moment, so it will take up too much
space. And really, there's no need to have it there anyway - it's not
information you desperately need in the middle of an editing session.
Now we've got --version, that's an adequate way to find out the
version number if you really need it.


git-svn-id: svn://svn.tartarus.org/sgt@10266 cda61777-01e9-0310-a592-d414129be87e
Cope with the 'library' module being in a subdirectory.

When I migrate everything to git, it will stop being checked out
alongside tweak as it currently is, so I'm preparing for the build
script to still work in that situation.


git-svn-id: svn://svn.tartarus.org/sgt@10267 cda61777-01e9-0310-a592-d414129be87e
Remove dependency on Subversion keyword expansion.

The version number is now inserted into the Halibut doc files by the
build script.


git-svn-id: svn://svn.tartarus.org/sgt@10268 cda61777-01e9-0310-a592-d414129be87e