parse dependencies from meson.build file about nix-init

[milahu]

cheap win: parse project version from meson.build file

example:
https://github.com/frida/vala/blob/62ee2b101a5e5f37ce2a073fdb36e7f6ffb553d1/meson.build#L1

project('vala',
	'c', 'vala',
	version: '0.58.0-frida',
	meson_version: '>= 0.47.0',
	license: 'LGPL2.1'
)

in this example, the project has no git tags (see also #19), so when using the latest commit, the version would be something like unstable-2022-11-07

a version like 0.58.0-frida-unstable-2022-11-07 is more useful to see API/ABI compatibility (semantic versioning)

see also RFC 107