Simplify logic for setVerbose in REPL
Cosmetic tweak in interactive editing
Induction on nat working
Improvment on readability and usability of induction and eliminators.
Fixed reflection induction tactic
Readded solveAll
Remove superfluous function

maybeToList is merely an instance of toList
Recursive constructor disjointness + cleanup
Default superclass intances

This allows code like:

    data Identity i = Id i

    class Functor (f : Type -> Type) where
      map : (a -> b) -> f a -> f b

    class Functor f => Applicative (f : Type -> Type) where
      instance Functor f where
        map f fa = ap (pure f) fa
      pure : a -> f a
      ap : f (a -> b) -> f a -> f b

    instance Applicative Identity where
      pure = Id
      ap (Id f) (Id a) = Id (f a)

    data Nat = Z
             | S Nat

    x : Identity Nat
    x = map S (Id Z)

Note the default Functor instance defined as part of the Applicative
class. This allows the Identity data type to omit an explicit Functor
instance and one gets defined from the Applicative instance.

This feature is largely copied from the approach done in She:

https://personal.cis.strath.ac.uk/conor.mcbride/pub/she/superclass.html

It basically does macro expansion of each default superclass instance
(e.g. Functor) when the containing class (e.g. Applicative) gets an
instance defined. Currently, default superclass instance definitions
are not type-checked, only their macro expansions are.

Default superclass instances are limited to being defined for types
which are syntactically equal to one of the superclass constraints.
Merge branch 'master' of github.com:idris-lang/Idris-dev
(Temporarily) Remove haddock tests from travis
Merge pull request #713 from ahmadsalim/feature/inductiontactic

Added support for induction tactic (works only for nonparameterized types insofar, requires eliminator for type)
Merge pull request #715 from Melvar/master

Remove superfluous function
Merge branch 'default-superclass-instances' of https://github.com/puffnfresh/Idris-dev into puffnfresh-default-superclass-instances
Merge branch 'master' of github.com:idris-lang/Idris-dev
Merge pull request #722 from puffnfresh/simplify-setverbose

Simplify logic for setVerbose in REPL
Merge branch 'forceability-cleanup-squashed' of https://github.com/ziman/idris into ziman-forceability-cleanup-squashed

Conflicts:
	src/Core/TT.hs
Update IBC version
Logic cleanup for REPL
Merge pull request #725 from david-christiansen/cleanup-repl-invoke

Logic cleanup for REPL