Changed World Map code

Changed the World Map code to follow better coding procedures. Also, the
field for each farm now chooses water plots randomly.
Merged from master
Sounds and Music 1.0

Sounds and Music play. Sounds play when most items are clicked though.
Methods for adjusting the sound and music in place.
Sounds and Music Finished and Commented
Merging from Audrey

Merge remote-tracking branch 'origin/AudreyBranch'

Conflicts:
	farm_adventure/src/com/aa_software/farm_adventure/model/Field.java
	farm_adventure/src/com/aa_software/farm_adventure/model/item/AbstractItem.java
	farm_adventure/src/com/aa_software/farm_adventure/model/item/tool/harvest/AbstractHarvestTool.java
	farm_adventure/src/com/aa_software/farm_adventure/model/item/tool/plant/AbstractPlantTool.java
	farm_adventure/src/com/aa_software/farm_adventure/model/item/tool/plow/AbstractPlowTool.java
	farm_adventure/src/com/aa_software/farm_adventure/presenter/screen/WorldScreen.java
	farm_adventure/src/com/aa_software/farm_adventure/presenter/screen/farm_screen/AbstractFarmScreen.java