libgnt/libgnt

Overhaul the convey builds

2021-09-27, Gary Kramlich
34678c8af458
Overhaul the convey builds

Testing Done:
Ran `convey debian-bullseye-amd64 debian-bookworm-amd64 fedora-34-amd64` and verified everything worked properly.

Reviewed at https://reviews.imfreedom.org/r/953/
option('doc', type : 'boolean', value : true, yield : true,
description : 'build documentation with gtk-doc')
option('introspection', type : 'boolean', value : true, yield : true,
description : 'build introspection data')