Changed dx,dy to private as they should have no need to be modified outside Ent$
Removed delta field of Entity as Entity should have no need to know the time si$
Updated frameMove method to take a single arguement (the time in microseconds s$
Made frameMove slightly more accurate for unintended fps ranges.
Added slick exception catching in main method with improved reporting.
Externalised magic numbers from main method to HelloGame static final fields.