* Allow block with separate type signature and definition of a function
For instance,
```
function
add : (int, int) => int
add(x, y) = x + y
```
cc #196
* Allow pattern matching in left-hand sides
* Changelog
* Fix type spec
* partial case-on-constructor
* Changelog for pattern-matching lets
* Add opcode for ecrecover
* Update aebytecode
* Extend signature bytes type used for ecrecover
* Add ecrecover to changelog
* Add some type specs
* Please dialyzer
* 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
Because `qid` was not accepted the following code
```
contract Test =
datatype myOption('a) = MyNone | MySome('a)
entrypoint optionFn(v: myOption(string)): myOption(string) = v
```
Used to lead to `function_clause` error.
Bug copyright (c) @nduchak
Problem: having public as the default makes it very easy to accidentally
export local function by forgetting the `private` modifier.
Solution: functions are private by default and must be declared as `entrypoint`s
to be exported. So `entrypoint foo() = ...` instead of `function foo() = ...`.
We still accept the `private` modifier although it is redundant.
