fix screenPhysicalPixels error

[Podspec] Set podspec version from the package.json and fix git source in the Podspec

Support fullscreen mode

Add naturalSize to callback

Update README to explain where android assets go

[Podspec] Read version from the package.json, add author, add tag to the git source, add .git extension

We need them to be able to present another view controller

Update README.md

support content:/ uri in android