Indents legends
CDB-1243 #resolve - added help tip for legends panel + html colors for infowindow and legend html editor
CDB-1243 - added xml codemirror file to js files in grunt process
Merge pull request #432 from CartoDB/CDB-1243

Several fixes for the legends panel (indentation, codemirror config, help tip, etc.)
Merge branch 'master', remote-tracking branch 'origin' into CDB-2590