2014-09-02: Added tag v0.6.4 for changeset 1c63ac211fe4 stable

Added tag v0.6.4 for changeset 1c63ac211fe4

diff --git a/.hgtags b/.hgtags
--- a/.hgtags
+++ b/.hgtags
@@ -20,3 +20,4 @@ 5475d743562512c44d2cdd0bf534c78c88efb0f8
 64745a296d569849de536000b636c100e3e0d30c v0.6.1
 7089c2ba36f5b3f1eeafde42be4ca4e4df1d6544 v0.6.2
 fc3d17fe770257a5e700c912844cee14668aa431 v0.6.3
+1c63ac211fe4275a00f7e206c7f44051e0d7cd81 v0.6.4