Initial import of package org.newdawn.slick.command.*

From development branch, change set 96a4b840204c65241d5bf81afbb4eead5f25c57f
See: https://bitbucket.org/kevglass/slick
Brought in code to compile org.newdawn.slick.command.*

From development branch, change set 96a4b840204c65241d5bf81afbb4eead5f25c57f
See: https://bitbucket.org/kevglass/slick
Replaced tab with four spaces.
Using generics.
Used Eclipse's auto code generator for hasCode and equals.
Added final keyword where applicable.
Weakened access level based upon IntelliJ's suggestions.
Fixed unbinding of command.
Removed unnecessary casts.
Fixed Javadocs according to Checkstyle.
Added override annotation.
Used Eclipse's auto code generator for hasCode and equals.
Fixed spelling errors.
replaced for foreach loops.
Using lambda.
Javadoc checkstyle fixes.
Removed version file.
Using generics.
Fixed spelling errors.
Removing redundant cast.