0.0.1~beta2

CHANGES:

• Composition between Miou and user-defined effects. @dinosaure
  664e8e26ec861c4fe3672144eead70b42f5fdbe5

  Miou includes a mechanism that allows you to create an effects manager using
  Miou's effects manager. The latter always respects the rule: one effect
  yields. The documentation has been updated accordingly. Tests 28 and 31 show
  an example of effect composition.

• Integrate the test t26 & t27. @dinosaure
  885d86eeedede3b28f6467bc2f0343b2ccf71225

  Test 26 verifies that Miou does indeed perform an infinite loop if a system
  event handler has not been installed and Miou.suspend is used. Test 27 is
  used to check Miou's behaviour with Miou.yield.

• Fix the happy-eyeballs example & cancelled suspension points. @dinosaure
  ffa2fc059d62bf580ed6d090aaf33e26fe9571e8
  bf47c1a83ad5b8607dd097b6a1547cc18c0527c8

  When a task is cancelled, we have to clean up the suspension points created
  in this task. The code has been factorised to avoid duplication between
  happy-eyeballs and dns.

• breaking change Be able to know if an orphans still have few tasks or
  not. The Miou.care returns an 'a t option option where:

  • Some (Some _) is a ready-to-await task
  • Some None informs that some tasks still exists but they are not finished
  • None informs that the orphans has no more tasks

  @dinosaure
  0560a14ea848466ea99792d27138c47f71aab747

• Protect the dom0 from user's exceptions. @dinosaure
  0dd647e15a859d458d6daf3ca96e3e65a30ce30f

• breaking change The give argument no longer transfers ownership to the
  new task, but copies ownership so that the task that created the new task
  and the new task have ownership of the resource. @dinosaure
  55ff54ddfd585f52fcda4d56caf2458760a7f949

• Add Miou_unix.shutdown (like Unix.shutdown). @dinosaure
  7f37ed6645965552a34070b23177dfdc4dda01fd

• Clean shutdown of the domain pool if one of the domains raises an exception.
  @dinosaure
  27f3d1d09a170212ab291daad214da3511d972a4

• Add a self function: This function lets you know which promise you're in. It
  provides information such as the domain executing the task, the promise
  identifier and the number of resources it is responsible for. @dinosaure
  0b1833f623e61b674105cdced64aa624f2a6340e

• Expose partially our Logs module. @dinosaure
  e4062178f4dee18a97fbc3ebb6fb36352d9ff9f5

• Be able to handle multiple suspension points for the same file-descriptor.
  @dinosaure
  1728d2600d0177f9422474bb41a1f12a111e6658

• Use Heapq instead of an Hashtbl to handle sleepers. @dinosaure
  32e0b8adc7a6a92e14dae12d1fa1991ce41f71a5

• Avoid CSE optimisation via Sys.opaque_identity. @polytypic @dinosaure
  5bcdaf4dd4fbf404cfb6f89b06280e12298c50cc

• Reverse control of task waits. Previously, Miou systematically added a step if
  we wanted to wait for the result of a task. If the task was completed, we
  ended up giving the result after several observations of the promise, which
  could be slow in certain situations.

  Now, waiting for a task attaches the continuation to the promise. If the task
  associated with the promise finishes, we simply "continue" with the value
  obtained avoiding a systematic observation of the state of the promise until
  the task finishes.

  @dinosaure
  d795f08fc64f3e53077172dbfedfcefe47a2b832
  42ef35bafa21ea0c264f6f3519fcb72732c1abd8

• Expose [Miou_unix.on_{read,write}]

  @dinosaure
  27174019f959414051bfbdb5057a17e6b7a036ee

• Fix the documentation about [Miou.call] and the possible situation where no
  domain are available to execute a parallel task

  @dinosaure, @zapashcanon
  aab9996ab2a3a59db2fed59f8ed997ef6f5abe14