GitLab

- add influxdb_bind_hostname var (defaults to ansible_hostname )
- deal w/ config format changes

Modified cluster purge logic slightly (due to extra/dirty data being kept in the WAL). Added sane, non-destructive defaults.

Added extra configuration flags for meta/clustering update. Changed default storage engine to tsm in preparation for the 0.10.0 release.

Uncommenting storage engine from configuration, setting the default to the b1 engine until tsm is ready for prime-time.

Added extra flag to control whether InfluxDB should be started on install. Templates use 'influxdb' group when joining cluster, so all influxdb instances that need to be clustered must be part of that group (previously it was using all hosts).

Variables moved from vars/main.yml to defaults/main.yml.  Role variables that you wish to optionally override in inventory should be in defaults.

Variable names have been namespace to role as to not collide with other roles using similar names.

Templates and tasks have been update to use new variable names.