Releasetool and icons

[Sasszem]

Created a short script that automates the creation of APK bundles and releasing. Added icons for APK. Can you check this? Closes #22

[Sasszem]

• yes, all it does is downloading the windows build of Löve2D and packaging the .love file with it in a zip file (love-release does this)
• Yes, see the asset/apkStuff/res folder. They was all named "love.png", as that's the name of the default icon.
• It uses apktool and uber-apk-signer for the android build, which both need Java
• the android version uses the java of android

It also needs wget to download a few files (uber-apk-signer and the Löve2d APK).