ndx-pose 0.2.0 release

[rly]

@talmo I would like to make a 0.2.0 release with the latest changes and add ndx-pose to the NDX Catalog this month.

You noted a couple TODO and nice to have items in #24.
Do you want to make any other changes or do any testing before the 0.2.0 release? I think the nice to have items can wait for a future release.

[rly]

I will also review #5 and #13 before release.

[talmo]

Hey @rly,

Nope, nothing on the ndx-pose end, but we'll be working to update sleap-io to support the training data very soon! (As well as a conda-forge release)