Convert to a noarch package and remove some old comments.

Remove kepler package that only works on Py 2 & required python-version-specific builds; Py 2 envs are now deprecated but can continue using the previous pyraf-all 1.0 build. This version of pyraf-all now only installs pyraf + iraf, for backward/forward compatibility.

Remove unnecessary build deps, since they are really run-time deps, which conda-build now checks anyway.

Disco_stu is now incorporated into dragons.

Constrain max sqlalchemy until code is updated for new v2 API and max specutils on Python 3.7, because v1.9.1 incorrectly allows installation there.

Stop requiring run-time deps at build time, since conda-build now checks that they can be satisfied anyway and it complicates things.

Make testing dependencies optional (they were incomplete anyway).

Include licence files in meta.yaml and use Jinja template for version etc.

Use newer pip install command (otherwise get pkg_resources file collision err).

Handle exit status more cleanly.

Add recipe for new gemini_obs_db package (v1.0.27), similar to gemini_calmgr.

Consolidate simple build scripts into meta.yaml & use template for version etc.

Convert packages to noarch since they are pure Python (otherwise we'd need 16 builds).

Use DRAGONS 3.1 version constraints, limiting sqlalchemy to <2.0 until the code can be ported to the new API.

Add constraints needed to avoid problematic dep versions from conda-forge.
Re-order some deps that were out of alphabetical order, for easier comparison with lists currently kept elsewhere (for testing).