Symlink of existing "Enyo Sampler" folder, for app renaming

There are hard-coded references to the "Enyo Sampler" folder
(reasonable) but since we have to rename it "Enyo Companion" to be
accepted into the iOS App Store, we have a symlink called "Enyo
Companion".
Sampler -> Companion

Replace various "Enyo Sampler" files with their "Enyo Companion"
equivalents for the iOS project.
Ignore generated files

We don't need to check in the generated index.html or cordova lib.