Update 0.10! (difficulty options, freeroam etc.)

Changelog:

• added a basic main menu
• added difficulty options on the main menu with easy and hard mode being available from the start (hard mode is what the difficulty was before this update), and a freeroam mode unlockable after completing either of the other modes 
• quitting from the level now takes you back to the new main menu 
• fixed an incorrect collectable dropping from a flying urn 
• fixed some incorrect textures in the final cave area

Enjoy!