I did my first pass on the help text.  so far the only help text is in my builder demo.

Changes include:

Input.cs
Added keybinding for H to bring up help text scene if it exists.

main.cs
added exec("./scripts/helpText.cs");
Added cleanup for the help text screen during LeapToy::reset and LeapToy::destroy

builderDemo.cs
Added the missing legal text at the top.
Added script to create the helptext simset and create a helptext scene with it.
Changed the CenterZ value.  Felt like it needed to go back a bit.

helpText.cs
Added helpText script file with create, toggle, and clear functions