[ Issue 1375 ] Fixed by more precise SIZELT analysis of clauseTel.

TODO: Make analysis even more precise.
[ Issue 1375 ] Variations on a test case.
[ testsuite ] Silenced succeed/Issue1345 (no debug output!).
Merge branch 'maint-2.4.2'
[ issue 1293 ] Cosmetic changes
[ issue 1293 ] Show instance not used any more when reporting errors.

The instance is

  instance Show a => Show (Position' (Maybe a))

from Agda.Syntax.Position.
[ issue 1293 ] Added TODO
[ issue 1293 ] Replaced show function by pretty
Merge remote-tracking branch 'my-agda/issue-1293'

Conflicts:
	src/full/Agda/TypeChecking/Errors.hs
[ .cabal ] Added lower bound for the parallel library

(Travis uses parallel 3.2.0.4 with all the versions of GHC)
Merge branch 'maint-2.4.2'
[ refactor ] Removed useless expandEllipsis from ConcreteToAbstract
(Ellipsis are already expanded in Syntax.Concrete.Definitions)
Merge branch 'maint-2.4.2'
[ Issue 1379 ] Fixed the range of with clauses starting with an ellipsis.
[ refactor ] Removed unused last argument from SplitError.CantSplit.
[ refactor ] Use whenJust and <.>.
[ comment ] Agda.Utils.NubList is UNUSED.
[ new ] Agda.Utils.Singleton replaces Agda.Utils.Pointed.

Overloaded method `singleton` constructs singleton collections of
various types.  Analogous to Agda.Utils.Null.
[ Issue 1084 ] Fixed by removing function names that do not appear in offending calls.

Termination errors should now only be reported for functions that
actually contribute to potential cycles.
[ Issue 1084 ] Updated error messages in test/fail.