General: Fix for refresh icon in IE browsers, Fixes #657
added coveralls badge
Annotation: filter field is not interpreting in elasticsearch query, Fixes #661
fix #660 by checking if options is undefined

- a complete fix with a consistent support of alias in all use cases is not obvious (see #660 for explanations)
updated changelog for PR #666, Closes #660
Cleanup legend value by using css content
Merge branch 'legend-value-cleanup' into er.mohw
add custom css