* Update utils.get_anymail_setting to support
kwargs override of django.conf.settings values
* Use the updated version everywhere
* Switch from ImproperlyConfigured to
AnymailConfigurationError exception
(anticipates feature_wehooks change)
Closes#12
Simplify install to just `pip install django-anymail`.
(Rather than `... django-anymail[mailgun]`
All of the ESPs so far require requests, so just move
that into the base requirements. (Chances are your
Django app already needs requests for some other
reason, anyway.)
Truly unique ESP dependencies (e.g., boto for
AWS-SES) could still use the setup extra features
mechanism.
(Prep for installing backends as package extras)
* Extract AnymailRequestsBackend and RequestsPayload
to base_requests.py
* Don't define/require requests exceptions when requests
not available
For MANDRILL_API_KEY (e.g.,), look for these settings:
* ANYMAIL = { 'MANDRILL_API_KEY': '...' }
* ANYMAIL_MANDRILL_API_KEY = "..."
* MANDRILL_API_KEY = "..."
(the "bare" third version is used only for settings that
might be reasonably shared with other apps, like api keys)
