relex-1.5.1 now available

Written for RelEx by linas on 2014-04-03

Provides assorted fixes and enhancements:

 * Extensive fixes for comparatives, from Rodas Solomon.
 * New TestRelEx.java adds more unit test cases.
 * Bugfix multi-language support.
 * OpenCog server can now return multiple parses.
 * Rename Inflection-TAG to Subscript-TAG.
 * Update Wikipedia processing scripts, including sentence splitter.
 * Add new rules for extraposition processing, from Rodas.
 * Add Vagrant support, for containerized build, install, run.