Plugin for making taxonomy releases

[brollb]

It would be good to ensure no nodes have been deleted on publish (and tag the current commit).

[brollb]

To flesh this out a little more, we need a plugin for making releases of a taxonomy. It should:

• take the type of release (major/minor) as a plugin config option
• determine the new version number (given above)
• add the version tag (and "latest") to the project
• if a minor release, ensure that no nodes have been deleted

[brollb]

naming conflicts might be good to detect, too

[yogeshVU]

• add naming conflict checking
• Add missing storage URL for the content-type https://github.com/webgme/webgme-taxonomy/issues/92

[brollb]

More documentation around taxonomy version bumping can be found here: https://webgme-taxonomy.readthedocs.io/en/latest/fundamentals/versioning.html