Implement in-table markup.

Specifically, the following are allowed:
 - Ordered lists
 - Unordered lists
 - Code blocks
 - NoWiki blocks
 - Lines of text.
Don't break the last list item in a table
Allow table cells to contain multiple InTable nodes, and define START for table cells to be whitespace-insensitive
Allow internal links to have a revision part
Allow the WikiWords token to include a revision
Fix REVIKI-491
Merge pull request #27 from Barrucadu/bad-acronym-detection

Fix REVIKI-491 (some links don't work)
Merge pull request #24 from Barrucadu/revision-links

Support revision links (PageName?revision=1234): https://jira.int.corefiling.com/browse/REVIKI-471
Add ANTLR jar
Merge pull request #28 from Barrucadu/antlr-jar

Add ANTLR jar.
Build ANTLR classes
Generate sources in a different directory
Merge pull request #29 from Barrucadu/gen-src

Generate ANTLR classes
Merge pull request #26 from Barrucadu/table-markup

Allow various wiki markup in table cells.  https://jira.int.corefiling.com/browse/REVIKI-341
Add DirectiveNodes, which render to nothing.

The purpose of DirectiveNodes is to turn modes off and on in the
renderer. At the moment, they do nothing, but possible directives would
be things like table cell alignment.
Give toXHTML() the currently enabled directives.

This shared state is updated when DirectiveNodes are rendered.

This is messy, as it involves passing around mutable state. A better way
would be to have a visitor for rendering, which handles this in a
central place. When I get on to adding multiple output formats, that's
the approach I plan to take.
Implement a directive for table cell vertical alignment.

Adds a directive `table-alignment` which assumes (at least, but more
ignored) one argument, which is a valid value for the CSS vertical-align
property. To be more forwards-compatible, it should probably be "top",
"middle", or "bottom".
Add DirectiveNodes to the visitor