chore(MADEWITHVRTK): add new game to list and reorganise on location
chore(MADEWITHVRTK): add new game to list and reorganise on location

A new game has been added to the list `ObserVR` and the list has also
been rearranged so all games on steam appear first and then all other
game locations are grouped together to provide easier visibility.

gpvigano/VRTK,thestonefox/VRTK,virror/VRTK,gpvigano/SteamVR_Unity_Toolkit,Innoactive/IA-unity-VR-toolkit-VRTK,gomez-addams/SteamVR_Unity_Toolkit,TMaloteaux/SteamVR_Unity_Toolkit,Fulby/VRTK,mattboy64/SteamVR_Unity_Toolkit,adamjweaver/VRTK,red-horizon/VRTK,thestonefox/SteamVR_Unity_Toolkit