* Lossless image optimization (using ImageOptim).
This shouldn't change the visual appearance of any images. ImageOptim
was run with the highest compression setting except that JPEG metadata
stripping was disabled because some users prefer to avoid stripping
JPEG metadata.
* Update READMEs that have Changelogs for themes impacted by lossless image optmization change.
* Update header-front.php
Add top margin.
* Update copy.
Update copy in subscribe and home patterns to something more generic.
* Update theme screenshot
* Update screenshot.png
