jared_sprague's sandbox: Compressed Cache

Adds gzip compression to cache data. Especially useful for sites with large amounts of cache_form data.

## INSTALLATION ##
1. Edit settings.php and add the following lines:

# Add this cache to the list of available cache implemntations
$conf['cache_backends'][] = 'sites/all/modules/compressed_cache/compressed_cache.inc';

# Add cache bins that you want to compress
$conf['cache_class_cache_form'] = 'CompressedDatabaseCache';

# Optoinal gzip compression level between 1-9. Lower level adds less compression but
# is faster, higher level compresses more but is slower. Compression
# level greater than 6 buys very little. Default value: 6
# $conf['compressed_cache_gzip_level'] = 6;
#
# If you want to compress all cache bins you can set the default class.
# This is not recommended. It's safer to only compress specific bins
# with large amounts of data i.e. cache_form
# $conf['cache_default_class'] = 'CompressedDatabaseCache';