Improve mouse handling

[szapp]

Instead of relying on the cursor package of LeGo (which is just another dependency), the mouse handling can be done more straight-forward.

Change this line

var int deltaX; deltaX = mulf(mkf(Cursor_RelX), MEM_ReadInt(Cursor_sX)); // Get mouse change in x

into

var int deltaX; deltaX = mulf(mkf(MEM_ReadInt(mouseDeltaX)), MEM_ReadInt(mouseSensX)); // Get mouse change in x

And add these constants:

const int mouseSensX = 9019720; //0x89A148
const int mouseDeltaX = 9246300; //0x8D165C

[szapp]

This was actually never fixed. It does not seem to work. Instead free aiming will now just have to depend on LeGo_Cursor

[szapp]

Fix #11, #14, #15, #16 and clean up code