Add logo option to ol.source.Source
Add logo option to ol.source.Source subclasses
Configure logo for Bing Maps source
Configure logo for MapQuest sources
Add logos to frame state
Update logos in renderers
Add ol.control.Logo
Add logo control by default
Merge pull request #480 from twpayne/logo-control

Add logo control
Sort src/objectliterals.exports
Merge pull request #483 from twpayne/sort-objectliterals-exports

Sort src/objectliterals.exports