Cleaned up python bindings interface a bit; now returns strings rather than character codes if appropriate

kindasorta working. all tests (except h_action and h_attr_bool, need typemaps) have passed at one time or another, but some segfault at not-quite-random; h_and, h_epsilon_p, h_end_p, h_ignore, h_not, maybe h_choice seem culprity.

h_sequence, h_choice and HCountedSequence are all having weird issues, but tests are in a workable format now

There's a typemap problem between const uint8_t* and target-language strings, but I can create parsers in python and php.

Import combinator and allocator APIs into SWIG. Next is glue. Need to fix unions in HParsedToken and HCaseResult.

 * "in_" and "not_in" should coerce their results to strings (i.e., chr(result))
 * TestLeftrec: success case 2 fails
 * TestChRange: success case segfaults
 * TestWhitespaceEnd: success case segfaults
 * TestAction: success case segfaults with "corrupted double-linked list"
 * TestButNotRange: segfaults, probably because of whatever's wrong with ch_range
 * TestXor: segfaults; failure case craps out with "malloc(): smallbin double linked list corrupted"

Add void* userdata to callbacks

Allow in-place build via scons --in-place

Make install_name darwin-only

Changes for doing a proper system install and Go bindings

Specify warning for internal only headers that are now installed for use
by extensions.

Reduce IRC spam

This actually is only for OS X. On linux ldconfig must be run after
installing in order to update the library cache. Need to look into how
to get scons to do this for the user.

Set the proper path for the shared library so that anything linking
against it will be able to find the library.