Add functionality to download AGPS data

Signed-off-by: mvglasow <michael -at- vonglasow.com>

Conflicts:

	AndroidManifest.xml
	res/menu/main.xml
	src/com/vonglasow/michael/satstat/MainActivity.java
Sky plot: show only satellites with valid ephemeris. Fixes #8

Signed-off-by: mvglasow <michael -at- vonglasow.com>
Sky plot: don't push other views off-screen. Fixes #6. Thx jkufner/paulle

Signed-off-by: mvglasow <michael -at- vonglasow.com>
Add support for 5 GHz WiFI frequencies. Fixes #9. Thanks maugsburger!

Signed-off-by: mvglasow <michael -at- vonglasow.com>