implement serializers
expose documentation of serializers
implement aggregation
ensure that str are yaml friendly
document aggregation
added reset tag
a little bit of lint
Made the shell shim compatible with AIX.
How to enable custom runners
Add zmqversion grain

Like saltversion, this grain can help show the effective version of a
particular component (in this case ZMQ) that is in use on the running
minion, and help aid in troubleshooting.
Check for None
Fix --list all option
Fix highstate output

Refs #10945
Fix issue 11020
Added exception and stack functions to the test module
Merge pull request #11018 from cachedout/10982

Fix --list all option
Added load_text filter and import_text tag to Jinja environment
Merge pull request #11004 from chevah/salt-ssh-aix-support

Made the salt-ssh shell shim compatible with AIX.
Merge pull request #11010 from terminalmage/zmq-grain

Add zmqversion grain
clear available pkgs cache when pkg db changes

Since repositories can be added in packages (indeed, this is the method
by which EPEL is recommended to be installed), this commit clears the
__context__ variable in which this information is stored, forcing it to
be recreated on the next call to check_db()