Add db loader type
Add keyring db type
Initialize db dir
Allow config.get to use db, add db helpers
Rename db to sdb, to avoid name conflicts
Initial documentation for SDB loader
Fix typos in SDB docs
Rename db doc dir to sdb
Remove unnecessary option from config.get calls
Mark SDB as experimental
Rename init
Linting
Rename saltdb in loader, to avoid confusion
Add docs for keyring usage
Add docs on writing SDB modules
Break out SDB functions from config module