talkatu/talkatu

Migrate to gi-docgen and remove the doc comments that were gtk-doc specific

Testing Done:
Build the docs locally and via the convey plan.

Reviewed at https://reviews.imfreedom.org/r/1056/
syntax: glob
*.pyc
*.ui~
\#*.ui\#
syntax: regexp
^artifacts\/
^build.*\/
^debian\/?
^packaging\/debian\/tmp\/
^packaging\/debian\/(.+\.)?(substvars|debhelper\.log)$
^packaging\/debian\/build.*\/
^packaging\/debian\/\.debhelper\/
^packaging\/debian\/debhelper-build-stamp
^packaging\/debian\/gir1.2-talkatu-0.0\/
^packaging\/debian\/libtalkatu0?(-.+)?\/
^packaging\/debian\/talkatu-demo\/
^packaging\/debian\/files$
^po\/.+\.pot$
^obj-.+\/
^old\/
^subprojects\/.+\/