Revert "Added F# SymbolHelper.fs. Fixed some of the highliighting."

This reverts commit 803d27bec8c7a384ab3d5525cb7b607df4a48368.
Revert "Tidied up code, simplified some logic"

This reverts commit 982d02fc80ef61cc65db30f6a88f2766acac3c55.
Revert "Fix prompt if default not found"

This reverts commit b6a713ab1acef85dd9898871a3211c77e7dc1c12.