Fix visarga bug in ITRANS

This prevents inserting extra '.h' tokens when transliterating to
ITRANS. This also prevents treating '.h' as '.' + 'h' when
transliterating from ITRANS.
Add WX support

The various WX charts online do not specify how WX encodes symbols and
punctuation. The current encoding makes some educated guesses.
Add WX to readme
Fix Telugu -> Devanagari bug

Telugu 'ka' and 'kha' were mapped to both Devanagari 'ka' and 'kha'
and Devanagari '.ka' and '.kha'. On checking various Telugu tables
online, I find that Telugu does not support '.ka' and '.kha' at all,
which means that those letters can probably remain unmapped.

(I'm not sure why this mapping was created in the first place!)
Add support for Oriya lR/lRR vowel marks
Update Oriya description
Clean up some comments and commas
Fix behavior when skipping SGML

For details, see the new test.
Remove extraneous block

The roman -> Brahmic case was addressed by the previous commit. The
other direction should probably be addressed eventually, but for most
SGML it's safe. (The exceptions are tags that contain Brahmic data.)
Rename project in README
sadf