Added missing 'get' for MonadState instances.

Signed-off-by: Gary Pamparà <gpampara@gmail.com>
Merge pull request #306 from gpampara/monad-state-get

Added missing 'get' for MonadState instances.
add using
add reader and writer instance
Merge pull request #309 from halcat0x15a/using-resource

add using
Merge pull request #310 from halcat0x15a/reader-writer-instance

add reader and writer instance
composeN aliases for `KTypeClass`
replace usage of `Either` by `\/` in `Task`
Eliminated race and subsequent pattern error from Future#chooseAny.

There was a race condition where the latches were released
before the result was set. This meant that the pattern on
line 285 fails. The failed pattern match resulted in an
exception and an eventual deadlock.

Fixes #308.
Merge pull request #312 from markhibberd/future-fix

Eliminated race and subsequent pattern error from Future#chooseAny.
Merge pull request #311 from larsrh/topic/task-either

replace usage of `Either` by `\/` in `Task`
replace usage of `Either` by `\/` in `Nondeterminsm`
update sbt-pgp and sbt-release, adapt build file accordingly
Setting version to 7.0.0-M9
Setting version to 7.0-SNAPSHOT
Added tests for Future.

This includes:
  - Monad laws
  - Regression tests for #312
  - Extracted some tools from ActorTest that
    are useful for testing scalaz-concurrency