* Fixed a bug in the fact search language parser where it would not loop
over all the <and, or> operations. The result, we can support (a=b or
a=c or a=d) also support (a=b and b=b and c=b)
* jsonbfield supports json querying. jsonfield package is still a jsonb
postgres data type, but doesn't support jsonb style querying.
* add undo migration support to GIN index
* Generating the set of valid unicode characters is expensive in terms
of memory storage. Instead, we define the grammer by the negation of
allowed unicode characters. Much faster.
* Establish a base grammar for handling json path specification and
value matching. With boolean logic support and parenthesis grouping
i.e. (a.b.c="value") and ((a.b="foo") or (a="bar"))
* generate Q() results for passing to Host.objects.filter()
* Hooked up via /api/v1/hosts?host_filter=...
* DynamicFilterField added to store host filter as string with grammar
parser attached as static methods for later use by DynamicInventory &
continued use by host_filter=...
