Aa-fleetpings

Added

- Checkbox to create an SRP link when SRP is active for a fleet and formup time is set
to "NOW". Supported SRP Modules:
- allianceauth.srp (that's the built-in module)
- [aasrp](https://github.com/ppfeufer/aa-srp)
- Colored box in the admin fleet type overview to represent the embed color

Changed

- Giving the ajax call a proper name

Removed

- Django 2 support

Fixed

- Bootstrap classes in template

Fixed

- An issue with quotes in the doctrine field ([38])

Fixed

- Create optimer is visible even if optimer is not active ([35])

Added

- "Don't Ping" option to ping targets

Added

- Checkbox to automatically create a fleet operations timer for a pre-ping