Added BuiltInSequence() Builtin

Handy function for bit more complex skinning stuff.
useful..
- when using $INFO[Skin.String(...)] or $VAR[] for < onclick > in skins (could make use of it in Nox)
- 2+ executes with one AlarmClock
- Keymaps (?)

Usage
BuiltInSequence(Builtin1,BuiltIn2,...,BuiltInX)