Fixed typos
[ issue 1283 ] Added missing type signatures
[ issue 1283 ] Fixed

* Added -fwarn-missing-signatures to Agda.cabal
* Removed {-# OPTIONS -fwarn-missing-signatures #-} from the modules.
Merge branch 'maint-2.4.2'

Conflicts:
	src/full/Agda/Utils/Pointer.hs
	src/full/Agda/Utils/Time.hs
[ .ghci ] Added -fwarn-missing-signatures