Added list comprehensions and standard List, Option, Func, Pair, and Triple library (#105)

* Added standard List library and list comprehensions

Added List library.

Flatmaps WIP

Fixed dependency in flat_map

fcode generation

Updated tests to use custom list lib

Added comprehension test

Added stdlib

sanity

Test

* Extended stdlib for lists. Added error message for redefinition of stdlibx

* Fixed type template

* Improved stdlib

* More functions

* Fixed cyclic includes

* Refixed imports and added few tests

* Added fail test

* Undelete removed type spec

* Remove typo

* Fix iter function

* Fixed typo

* Added if guards and let statements in list comp

* Added more fail tests

* Option stliv

* 2 and 3 tuple stdlib

* Updated stdlib to new syntax. Added recursor and changed all/any functions

* Fixed performance issues. Changed include management

* Fixed hash type

test/contracts/cyclic_include.aes

@@ -0,0 +1,4 @@
+include "cyclic_include_forth.aes"
+
+contract CI =
+  entrypoint ci() = Back.back() + Forth.forth()