concrete syntax: fix bug in parsing integers/floats.
ivory: remove cruft.
concrete syntax: remove unused var warnings for older GHCs.
ivory: bump ivory, ivory-backend-c minor rev ahead of hackage.
add Ivory.Language.Plugin

This is a GHC plugin that rewrites Ivory programs to insert source
locations referring to the original Haskell source. It currently
requires the -fhpc flag to get the source locations from GHC, but
that should change with the planned introduction of DWARF support
in 7.10.

See ivory-examples/ivory-examples.cabal for an example of the
options you should pass to GHC to enable this plugin.
clean up
add option to ivory-backend-c to not output srclocs
expose ensures_
update ivory-backend-acl2
Merge branch 'master' into ivory-model-check

Conflicts:
	ivory-backend-c/src/Ivory/Compile/C/Gen.hs
	ivory-examples/ivory-examples.cabal
	ivory/src/Ivory/Language/Monad.hs
	ivory/src/Ivory/Language/Syntax/AST.hs