Merge branch 'release/0.1' into develop
Add `Monad.Maybe.maybe/3` function
Change order of function definitions
Change order of tests
Add `Monad.Maybe.from_just/1` function
Rename variable
Add `Monad.Maybe.from_maybe/2` function
Merge branch 'feature/from-maybe' into develop
Add `Monad.Maybe.maybe_to_list/1` function
Add `Monad.Maybe.list_to_maybe/1` function
Add `Monad.Maybe.cat_maybes/1` function
Simplify macro expansion

There is no need to expand return statements: `return` can just be
imported into the local scope. Thanks to Peter Minten (pminten)
for the hint.
Make functions private
Change README to reflect recent change in macro expansion
Change order of macro and function definitions

The module now reads top-down.
Rename `m_do` macro to `m`
Fix typo
Add `Monad.Maybe.map_maybes/2` function
Tweak README
Bump version number