diff-lcs version 1.2.1 has been released!

Diff::LCS computes the difference between two Enumerable sequences using the
McIlroy-Hunt longest common subsequence (LCS) algorithm. It includes utilities
to create a simple HTML diff output format and a standard diff-like tool.

This is release 1.2.1, restoring the public API to what existed in Diff::LCS
1.1.x. Everyone is strongly encouraged to upgrade to this version as it fixes
all known outstanding issues.

Changes:

## 1.2.1 / 2013-02-09

* Bugs Fixed:
* As seen in https://github.com/rspec/rspec-expectations/pull/200, the
release of Diff::LCS 1.2 introduced an unnecessary public API change to
Diff::LCS::Hunk (see the change at
https://github.com/rspec/rspec-expectations/commit/3d6fc82c for details).
The new method name (and behaviour) is more correct, but I should not have
renamed the function or should have at least provided an alias. This
release restores Diff::LCS::Hunk#unshift as an alias to
#merge. Note that the old #unshift behaviour was incorrect and will not be
restored.