add information and link to DINAPy to API spec page

[low-decarie]

Add to https://www.dina-project.net/en/docs/api-specs

Specify that main use of API is through DINA GUI.

Add link and information about https://github.com/AAFC-BICoE/dina-py

[dshorthouse]

Can dina-py be contributed to PyPI as is the DINA ruby gem to rubygems.org https://rubygems.org/gems/dina? Perhaps too the README for dina-py can be made more friendly with more examples like https://github.com/dshorthouse/dina.

Specify that main use of API is through DINA GUI.

Can you clarify what you mean by the above?

Note also that every page on https://www.dina-project.net/ has an "Edit this page" link at the bottom so you may submit a pull request with suggested changed to the md files.