Add tests
Fix typo
Tweak layout
Test monad laws for Maybe monad
Merge branch 'feature/test-monad-laws' into develop
Use shorter form of & operator
Use `do:` syntax for function definitions
Add `Monad.Maybe.just/1` function
Rename test module
Tweak test messages
Add `Monad.Maybe.is_just/1` function
Add 'Monad.Maybe.is_nothing/1` function
Add `Monad.Either` module
Run test cases concurrent
Add `Monad.Either.either/3` function
Extend .gitignore
Split tests
Add `Monad.Either.fail/1` function
Merge branch 'release/0.1'