Upgrade to Solr 4.7.0

Upgrade to Solr 4.7.0 with custom Yokozuna patches.

* Create custom 4.7.0 package that includes Yokozuna patches and
  upload to Basho's S3.
* Pull the new package.
* Remove stopword and other configuration files from source tree. Copy
  from package to stay in sync.
* Add Kurdish language support.
* Update to the latest Lucene 4.7 codecs.

See the commit messages for more info.

Note: The aae_test and yz_rs_migration_test will fail against this
PR. The migration test has been failing and the AAE test is related to
the segfault issue in eleveldb (basho/eleveldb#104).