pgmemcache: fix sasl build issues with gcc 4.8
.gitignore: added
extension: automatically versioning for the extension

Automatically set the ext version number based on the latest git tag.
pgmemcache: make binary protocol the default

Binary protocol is faster and exposes more features than the legacy ascii
protocol.  Binary protocol has been supported by memcached since version
1.4.0 (released in July 2009.)
pgmemcache: change memcache_incr/decr to use BIGINT arguments

This requires a version change as the schema was changed.
pgmemcache: release version 2.1.1
Merge pull request #11 from saaros/version-2.1.1

* Fix errors and warnings exposed by GCC 4.8
* Make the memcache binary protocol the default
* Change memcache_incr and memcache_decr to use BIGINT arguments for the
  increment/decrement values