third_party libs not included in release package

[dotKokott]

Any chance you would consider adding the third_party folder in the release archive?

Background: I would like to have the draco_transcoder be part of the conda package. Apparently conda-forge packages are only allowed to be build from published release URLs (not from a git url / tag, where I could pull the submodules myself). It seems the only option right now is to have the third_party submodules be included in the release package so I can build with transcoder support.