Why I did it
Quagga is no longer being used. Remove quagga-related code (e.g., docker-fpm-quagga, sonic-quagga, etc.).
How I did it
Remove quagga-related code.
**- Why I did it**
Align style with slightly modified PEP8 standards (extend maximum line length to 120 chars). This will also help in the transition to Python 3, where it is more strict about whitespace, plus it helps unify style among the SONiC codebase. Will tackle other directories in separate PRs.
**- How I did it**
Using `autopep8 --in-place --max-line-length 120` and some manual tweaks.
* [cfggen] Support reading from and writing to configdb
* [bgp] Move bgp_admin_state to configdb, support dynamic admin state change
* [sonic-utilities] Adapt configDB for admin status, support config save and config load
