Add switches to skip and ignore checkstyle.

This should probably go to airbase in the long run. This allows a
submodule to set air.check.fail-checkstyle to false for development,
therefore no longer need to constantly reformat and optimize the code
while developing.
Fix some warnings flagged by Eclipse.

static member access
overriding varargs with []

Closes #1411
Add lag and lead window functions
Control cassandra client timeouts

Closes #1435
Optimize json_size function

Avoid extra round trip by performing size directly in extract code
Use function binder to cache patterns in call site