Enrich the flot with the ability to add text into markings.
Adjust some indentation and use === instead of == recommended by Travis CI.
Add an 'aboveGrid' option to the markings for backwards-compatibility.
Fix the indentation issues.
Use !== instead of != as Travis CI suggests.
Use addText API to get rid of the redundant code; Update API.md.
Update some line ending issues.
Add a newline to the end of the file.