Adding support for S3 as a fileserver backend
Update s3fs.py
Update s3fs.py
Minor cleanups
[WIP] added cache expiry and fixing hashing
[WIP] File hashing and caching now working

Now just file_hash() and file_serve to fix up. Also need
to add some cache clean out code so old stale files will
be cleared when they are deleted from S3. update() seems
like a good place for this.
Feature complete s3fs.

It has proper file hashing, file caching, and it uses the same
credential settings as the other s3 utils/modules
call pkgin with full path avoids troubles when upgrading
Url encoded filename to fix handling of files with spaces
dir_list() implemented, fixed a few minor bugs

Still to implement file_list_emptydirs()
Add mine to toc, fix #4963
Merge pull request #4960 from Learnosity/s3fileserver

S3 file server backend support
Added salt.fileserver.is_file_ignored() support
Add virtual function for postgres user per #4967
Only load postgre_database state if postgres installed

per #4967
database, not user
Finish on fix #4967
Merge pull request #4981 from Learnosity/s3fs_is_ignored

Added salt.fileserver.is_file_ignored() support to s3fs
/etc/default/rcS file does not contain UTC boolean value on Debian Wheezy, causes out-of-bounds exception when attempting to lookup given value
Since Wheezy /etc/default/rcS no longer contains UTC settings, now located in /etc/adjtime

Reference: http://forums.debian.net/viewtopic.php?p=451275