Don't really need this anymore
Formatting fix
Fix code that relies on type inference to be correct.
Add better support for exception handling and Scala "syntactic suger"

This all started when I realized there was some code repition around the concept of a top level AST. I also had reason to suspect that this meant a corner case was being missed. So I added a test case for that corner case. However the corner case turned out to be a little trickier to fix than simply factoring the code. But still, the fix coincides with a better factoring of the code I believe.

I took the chance to rename some things that believe could be better named.
Merge branch 'master' into presentation_compiler

Conflicts:
	src/main/scala/com/github/jedesah/codesheet/api/ScalaCodeSheet.scala