Added slower heart movement while holding cancel.

…s Sans.

…s overlapping a second platform. (Issue bootheidiot#4)

Changed the 'heart is on platform' check to be more forgiving.
Changed the alternate Confirm/Jump button from 'Space' to 'Return', to be in line with Undertale.

Changed menus so that they can only perform 1 input-related action in a single frame.
Changed menus so that the menu display text isn't created 1 frame late.
Fixed a minor animation error when starting endless mode phase 2.

…pearing. (#18)

Added screen shake + final attack slam damage. (#16)

Made Gaster Blaster blast effect more accurate (#28)
Gave the Heart a 4x4 hitbox.

Added labels to custom attacks.
Made sans_bonegap2 attack more accurate.
Made sans_bonegap2 variant in multi-attacks more accurate.
Other minor accuracy fixes.

Added partially working update check.

Fixed gaster blasters still being able to damage you during a black screen.