Allow Postgres SSL

[mmomjian]

Fixes #744

Has not been tested locally as I am unsure how to deploy the source.

[mmomjian]

If this is added, we could use docker with the environment var DB_OPTIONS: "{'sslmode': 'require'}". We could be more specific with creating a flag to specifically enable this variable, but adding an envvar for OPTIONS would seem to be more future-proof.

[coveralls]

coverage: 98.773% (-0.02%) from 98.791%
when pulling 969dec0 on mmomjian:master
into bdeb149 on babybuddy:master.

[cdubz]

Thanks for contributing! Can you update your PR to also add a note about this to the database configuration section?

[mmomjian]

I have added a section in the documentation, thanks.

[mmomjian]

I also noticed that the documentation states that the default DB_ENGINE is django.db.backends.postgresql, but base.py seems to default to sqlite: "ENGINE": os.getenv("DB_ENGINE") or "django.db.backends.sqlite3". I made updates to the documentation to reflect this.

[cdubz]

Merged -- thanks for contributing!