Merge branch 'dev'
Adding cloning instructions
Fixed indenting for title
Removing require.jquery
Only clicks registered within the game area can call the fire function
Merge branch 'dev' into feature/config-options
Removing unused enemy property
Merge branch 'dev' into feature/config-options
Setting gravity, player density and enemy bounciness via range sliders
Adding config handler to listen for slider changes and amend the internal
game properties.
Adding config handler as dependency
Adding jquery-ui slider and script to use as a pseudo polyfill.
Adding default styles for jquery-ui slider
Fixing styles for range polyfill
Merge branch 'fix/range-polyfill-amends' into dev