[#230] Add `hoistMaybe` and `hoistEither` functions

[gpevnev]

Description

Problem: Currently to lift a value ma :: Maybe a into MaybeT m a you need to write MaybeT (pure ma), which is bloating code with unnecessary boilerplate. Same idea applies for Either e a and ExceptT e m a. `

Proposed solution: Add functions hoistMaybe :: Applicative m => Maybe a -> MaybeT m a and hoistEither :: Applicative m => Either e a -> ExceptT e m a

Related issues

• Fixed #230

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[gpevnev]

@gromakovsky should I add it as a new minor version (1.7.1 for example)

[gromakovsky]

If I understand PVP correctly, yes. Typically we write Unreleased in the changelog and replace it with the actual version when a new release is ready to be made, but in this case I suppose we can release 1.7.1 right after merging this PR.