Add Lambda alarms and suggested config for it.

[Sveder]

(Sveder: This is still a WIP. Opening PR to see that all tests pass in Travis. Leaving the instructions below to go over once the PR is done.)

Description

Added configuration for and the creation and deletion of cloudwatch alarms to Lambda and ApiGateway (WIP) automatically.

GitHub Issues

#1348

[Sveder]

@Miserlou WIP, but I'd love pointers, especially on if you like the config additions (in example/zappa_settings.json).

Todos:

1. Add cloudwatch alarms.
2. Add docs about the new config.
3. Add tests.

[coveralls]

Coverage decreased (-0.3%) to 73.787% when pulling 54e3e61 on Sveder:'feature/cloudwatch_alarms' into 2d1f253 on Miserlou:master.

[Sveder]

@Miserlou Any update on this?

[Miserlou]

Is this ready for review?

[Sveder]

@Miserlou Do you want me to add unitests before you look at it? Or do you want to give me some general guidance and I'll add the changes with the unitests?

[mascot6699]

@Miserlou @Sveder I would like to take this up if we can have clear expectations set.