Merge branch 'master' of github.com:populr-themes/cumberland

* 'master' of github.com:populr-themes/cumberland:
  update button & icon mixins; remove units from line-height properties
  Update text colors for first columnizer row
  Remove improperly commented-out code
  Fix extra padding on size 1 & 2 image asset titles
  Update theme thumbnail
  Add rounded corners to images
  Fix residual white space when size 3 image assets have title & description turned off in first columnizer row
  Add new mixins for .link-button, .icon, .inline-logo-title
  Fix styling for assets in hero area
fix exponential adding of magnifying glass