level with STIX versions in the same format as is used everywhere
else in the API: "X.Y", as opposed to the "vXY" format used by
the version-specific python packages. This eliminates all of
the awkward conversion from public API format to "vXX" format.
Also a little bit of code rearranging in the registration module
to ensure that some STIX 2.1-specific checks are done whether
version 2.1 is given explicitly or is defaulted to.
In the same module I also added a missing import of
stix2.properties, since my IDE was claiming it could not find a
function from that module.
- stix2.registry, which contains the class mapping structure
and code for scanning stix2 modules for its initial population
- stix2.registration, which contains code used to register custom
STIX types with the registry
- stix2.parsing, which contains code for creating instances of
registered stix2 classes from raw dicts.
This is intended to reduce circular import problems, by giving
dependent code the ability to import a module which has exactly
the functionality it needs, without pulling a lot of other stuff
it doesn't need. Fewer imports means less chance of an import
cycle.