Repl in command line

[ice1000]

C:\Users\ice10\git-repos\Arend\Arend\cli\build\libs>java -jar cli-1.3.0-full.jar -i
λ 1 Nat.+ 1
1 + 1
λ :whnf 1 Nat.+ 1
2
λ :nf 2 Nat.* 3
6
λ :type 1
Nat
λ :type idp
\Pi {A : \Type} -> \Pi {a : A} -> a = a
λ a
[ERROR] Repl:1:1: Cannot resolve reference 'a'
λ \func test => 1
λ test
test
λ :t test
Nat
λ \func test2 => test
λ :t test2
Nat
λ \func id {A : \Type} (a : A) => a
λ :t id
\Pi {A : \Type} -> A -> A
λ id 1
id {Nat} 1
λ :whnf id 1
1

Resolves #135

[ice1000]

TODO: add completions, help message