add 7za for making tuff less tuff

7za binary

 Changes to be committed:
	modified:   configs/common.mk
	new file:   prebuilt/common/xbin/7za
apk update, removed su+supersu

using superuser. removed unicorn porn

 Changes to be committed:
	modified:   configs/common.mk
	modified:   prebuilt/Android.mk
	deleted:    prebuilt/common/app/SuperSU.apk
	deleted:    prebuilt/common/app/UnicornPorn.apk
	modified:   prebuilt/common/app/XposedInstaller.apk
	deleted:    prebuilt/common/xbin/su
fix copy line

...

 Changes to be committed:
	modified:   configs/common.mk