update release history and version

Former-commit-id: 38caeb2d6a775d158ecf998228e723f0482b0aef

RELEASE_HISTORY.txt

@@ -1,3 +1,4 @@
+0.2.2  More explicit instanciations, faster sorts and uniques
 0.2.1  Bug fixes in barycenter and doublearea found by Martin Bisson
 0.2.0  XML serializer more stable and fixed bug in remove_duplicate_vertices
 0.1.8  Embree and xml (windows only) extras

VERSION.txt

@@ -3,4 +3,4 @@
 # Anyone may increment Minor to indicate a small change.
 # Major indicates a large change or large number of changes (upload to website)
 # World indicates a substantial change or release
-0.2.1
+0.2.2