Scaled down images for (presumed) handhelds

Increases scroll performance and allows things to load in faster
Adjust font colours on panoramic slides

Font was slightly blue, it was annoying!
Responsive redo

Fixes #14, fixes #12

Properly testing the site against iPads and Nexus 5s, defining a few proper breakpoints.
Ignore sublime text project files
Update readme

To-do list is irrelevant and handled by issue system
Merge pull request #15 from willmorgan/pulls/mobile-fixes

Mobile fixes