FLUID-5002: fixed paths to OpenSans-Light.tiff
FLUID-5002: Adjusted the font weight and size

Adjusted the font size and weight to match the designs. There is still an issue of the adjusting the font size for the labels of the checkboxes inside of the panels, but this results in some other styling issues. I file this as a separate issue.
FLUID-5002: Added missing font weights.

There were actually specific font files that could be used for each of the specific weights. Some browsers are able to fake this, but chrome would not. I've added in the missing ones for the weights we use and updated the css for it.
Merge remote-tracking branch 'jobara/FLUID-5002'

* jobara/FLUID-5002:
  FLUID-5002: Added missing font weights.
  FLUID-5002: Adjusted the font weight and size
  FLUID-5002: fixed paths to OpenSans-Light.tiff