brings the build in line with core
world-first attempt at palladium macros
scala.reflect.eval => scala.reflect.internal.eval
better synthetic shape to represent parsed macros
scala.reflect.hosts.scalacompiler => scala.reflect.internal.hosts.scalacompiler
makes things work correctly in REPL
makes the scalahost business more precise

We actually need two kinds of scalahosts: one that's created from just Global,
and another one that's created from MacroContext.

Also this commit fixes the need to cast cake-based inputs and outputs to
contexts by using the standard [G <: Global] type parameter technique.
adapts to the changes in HostContext
addresses pullrequest feedback
Merge pull request #1 from xeno-by/master

world-first attempt at palladium macros :)