Support for mulitple Blink sync modules

[fronzbot]

Description:

The blinkpy library added support for multiple sync modules with the most recent release, so I rolled those changes in here.

Example entry for configuration.yaml (if applicable):

blink:
  username: <username>
  password: <password>

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.

If the code communicates with devices, web services, or third-party tools:

• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.

[fronzbot]

Breaking Change:
Blink alarm control panel now inherits the name of the actual sync module rather than defaulting to blink_sync

[dgomes]

LGTM!

[fronzbot]

@dgomes anybody I should CC to get this looked at/merged? I feel like it has been lost in the shuffle and want to make sure it gets in before next release (it would be great if it was in the beta, actually)

[dgomes]

Sorry for holding this PR for so long :(

🎉