Fix: manifest[X].toString -> TypeStrings.fromValue

manifest[X].toString sometimes produces wacky strings that aren't valid
type names; TypeStrings.fromValue appears to behave better:

  scala> object A
  defined module A

  scala> manifest[A.type].toString
  res5: java.lang.String = A$@4d2aec21.type

  scala> scala.tools.nsc.interpreter.TypeStrings.fromValue(A)
  res6: String = A.type
Merge pull request #5 from jdanbrown/fix-wacky-types

Fix: manifest[X].toString -> TypeStrings.fromValue