libgit2/libgit2 — pull request #1011 by ethomson (2012-10-23 16:48:57+00:00)
Title: reset changes for merge

reset soft should fail if we're in the middle of a merge (as identified by the existence of a MERGE_HEAD file).

all other resets should clean up the MERGE_HEAD, MERGE_MSG and MERGE_MODE files. (ORIG_HEAD should be left untouched.)