Add support for match queries

Elasticsearch 0.19.9 renamed text queries to match queries. This
adds support for the new name.
Tweak .all note in CHANGELOG
Fix .demote() in regards to .query_raw()

If the dev has specified .query_raw(), that should cause EU to ignore
*all* things that modify the query clause of the search including
.query(), .demote() and .boost().

This fixes that, updates the test and updates the docs. While I was doing
that I fleshed out the docs for .boost() and .demote().
Tweak tasks docs and fix exception handling code
Docs overhaul

* move API docs to separate chapters
* make Django usage more prominent
* fix documentation issues
Docs overhaul 2: First Blood

* moves some theory stuff to a new theory chapter!
* clean up references (remove the parens)
* clean up documentation by focusing on sentences that are too dense
  "new idea"-wise
* removed a bunch of JSON because it's not very helpful to know and
  it's impossible to update
* broke things into sections so they're faster to find via tables of
  contents
* cleaned up the quickstart sample program
* nixed the big JSON blob thing
* moved documentation to docstrings in the code
* moved MLT to queries docs
Add a sillily high-level howto for integrating with Django
Cosmetic: Tweaks to docs headers
Move sample programs, write new intro
Tweaks
Reimplement queries

* add support for Q and combining Qs
* add support for explicit should, must and must_not clause specification
* add and update tests
* add and update documentation
Add documentation for Q, should, must and must_not
Tweak docs on boost
Add indexing documentation
Tweak docs for get_object and get_model
Fix typo
Change ElasticTestCase to ESTestCase

Seems to make sense to name it the same as the Django test case.
Create Indexable in core

* create Indexable in the core
* redoes the Django Indexable to only have the bits Django needs
* renames DjangoMappingType to MappingType
* adds a bunch of documentation
* adds new tests
Small change to make Indexable.get_es more usable by default
Cosmetic tweaks