- Also, explicitly fill `trial._id` with `Trial.NoID` during init.
- Minor renaming from self._type to self.type for getters in
  `Trial.Value`.
- Change representation of a `Trial` to better print out contained
  parameters.

Why:
   I need to way to identify saved stuff in local disk from the
   execution of my script given a particular trial. This way I can have
   a reproducible deterministic string identifier that I intend to pass
   appropriately to a command line argument (if specified from ``orion
   hunt``) of my executable. This will disambiguate saved states,
   snapshots, or logs (i.e. from tensorboard), among different trials of
   the same executable.

   The actual implementation of all save/load is left to the executable
   itself, as well as configuring the absolute path where the stuff will
   be saved to. Most (responsible) ML programs I have personally encountered
   have a cli way to specify some naming for the experiment to run.

- Replace name property
- Planning to match all flavours of experiment naming

Copy pasting from documentation of `SpaceBuilder.build_from`:
   This method is also responsible for parsing semantics which allow
   information from the `Experiment` or a `Trial` object to be passed
   to user's script. For example, a command line option like
   ``--name~trial.hash_name`` will be parsed to mean that a unique hash
   identifier of the trial that defines an execution shall be passed to
   the option ``--name``. Usage of these properties are not obligatory,
   but it helps integrating with solutions which help experiment
   reproducibility and resumability. See :attr:`EXPOSED_PROPERTIES` to
   check which properties are supported.

 - `SpaceBuilder.userargs_tmpl` is now an OrderedDict.
 - Built command line args respect **the order** and **the way**
   in which they where parsed.
 - Less acrobatics regarding configuration file path.
 - Tackles the cases where ``~`` in a cli arg means home folder as
   in a shell path name.
 - Logs warning wherever implicit arguable decisions are taken.
 - TODO: First positional may not be a config file => it's a bad
   restriction.
 - TODO: Import parsing regex elements perhaps from a orion config file

Copying from documentation of `SpaceBuilder._build_from_args`:

   Build templates from arguments found in the original cli.

   Rules for namespacing:
      1. Prefix ``'/'`` is given to parameter dimensions.
      2. Prefix ``'$'`` is given to substitutions from exposed properties.
      3. Prefix ``'_'`` is given to arguments which do not interact with.
         Suffix is a unique integer.
      4. ``'config'`` is given to user's script configuration file template

   User script configuration file argument is treated specially, trying to
   recognise a ``--config`` option or by checking the first positional
   argument, if not found elsewhere. Only one is allowed.

   .. note:: Currently positional arguments cannot define a parameter
      dimension. And I don't think they will; it wouldn't be good for
      your health down the line. Please be responsible and give a good
      descriptive name to your inputs.

  .. note:: Templates preserve given argument order.

Reason: MongoDB version changes, message in exception changes

I got greedy. Support it with a functional test.
Remove also dead code from ``SpaceBuilder._build_from_args``.
Add a test to show how it fails when it does.

Reason is that '/' means special thing in UNIX path names