[ prototyping/mixfix ] Relaxed some constraints to compile with ghc-7.8.
[ prototyping/mixfix ] Print error when benchmarks is called wrongly.
[ Sharing ] disableDestructiveUpdate in interaction and tryConversion.
[ Parser ] Refactor: Removed two uses of 'flip'.
Merge branch 'maint-2.4.2'

Conflicts:
	src/prototyping/mixfix/benchmarks/Test.hs
	src/prototyping/mixfix/benchmarks/mixfix-benchmarks.cabal
[ interaction test ] Updated output after disableDestructiveUpdate.