adding sound to road game, main menu
adding wav files
Added background music, mute/unmute functionality
updating credits
adding mohenjodaro credit
Added coin game sound effects
Merged master with sound branch
Fixed road game bug
Removed repetitive code
Merge pull request #26 from zsweedyk/fix-sound-conflict

Sound effects/music branch with conflicts with master resolved
Merge pull request #24 from zsweedyk/credits

Credits
Fixed Analye and OCLint warnings
Working through merge conflicts
SilkRoad/Images.xcassets/IndiaBlankMap.imageset/BlankMap-India.png