Graph reference 3.0:

- enable easily-configurable langauge-dependent
  meta description of graph objects.
- split `graph_objs_meta.json` output file
  into language folders (`./graph_objs/<lang>`)
- split setup, meta-generating functions,
  meta shortcuts and run command into seperate files
- replicate previous `graph_objs_mets.json`
- test for Python/Matlab dependencies
sketch doc_string integration in meta.py
Add specs to all graph object

- each graph obj now has 'docstring', 'links', 'examples' and
  'meta' fields. Before we had only the equivalent of 'meta'.
- 'links' list revelent links to our online docs
- 'docstring' is copied from e.g.
  https://github.com/plotly/python-api/blob/master/plotly/graph_objs/graph_objs.py#L1189
- 'examples' will have code snippet like
  https://github.com/plotly/python-api/blob/master/plotly/graph_objs/graph_objs.py#L1194
Handle example code snippets with MakeExamples() class

- add script/meta_examples.py
- copy examples from python-api docstrings
- move color and colorscale examples from meta_shortcuts.py
Update meta and meta shortcuts modules

- make ValTypes and RequiredCond classes
- add support for MakeExamples class
- add 'name' in graph obj *stuff*
  (e.g. to handle: Scatter in python, but scatter otherwise)
- remove .format() (now done in run.py)
- rename 'meta' to 'keymeta'
Update run.py

- add formatting function to handle all language-dependent vocabulary
- add *retrieve* function to handle language-dependent MakeExamples instances
modif tests for new json structure
add modified json files
No more NAME_TO_KEY and KEY_TO_NAME (sketch)

- add 'name' key (language-dependent name of a graph object)
- add 'obj_type' key (language-dependent object type)
- add 'parents' key (to what key is this object meant to be linked)
add support for all 5 langauges
update test_graph_references.py
add OLlike and ULlike to language_table
add important keymeta examples for all languages
add language table vocab to keymeta descriptions!
make meta_examples methods lower case
add write NAME_TO_KEY and KEY_TO_NAME
output of $ make run, now for 5 languages!
add formatting of a/an, A/An and plurals using inflect
remove graph_objs_keys.json and corresp write_() in run.py
output clean make run