chore(README): format title
chore(README): format title

Remove the underscores from the title for better readability.
Blueteak/SteamVR_Unity_Toolkit,red-horizon/VRTK,pargee/SteamVR_Unity_Toolkit,mimminito/SteamVR_Unity_Toolkit,Innoactive/IA-unity-VR-toolkit-VRTK,gpvigano/SteamVR_Unity_Toolkit,gomez-addams/SteamVR_Unity_Toolkit,thestonefox/SteamVR_Unity_Toolkit,phr00t/SteamVR_Unity_Toolkit,virror/VRTK,gpvigano/VRTK,adamjweaver/VRTK,nmccarty/htvr,thestonefox/VRTK,jcrombez/SteamVR_Unity_Toolkit,Fulby/VRTK,mbbmbbmm/SteamVR_Unity_Toolkit,thacio/SteamVR_Unity_Toolkit,TMaloteaux/SteamVR_Unity_Toolkit,mattboy64/SteamVR_Unity_Toolkit,bengolds/SteamVR_Unity_Toolkit,Frostlock/SteamVR_Unity_Toolkit