Log Message:
Update to 1.11.1:

The earlier libroff, libmdoc, and libman soup have been merged into
a single library, libmandoc, which manages all aspects of parsing
real manuals (from line-handling to tbl parsing).

Beyond this structural change, initial eqn functionality is in
place. For the time being, this is limited to the recognition of
equation blocks; future version of mdocml will expand upon this
framework.

As usual, many general fixes and improvements have also occured.
In particular, a great deal of redundancy and superfluous code has
been removed with the merging of the backend libraries.