switching back to "_all" as the nodes default
updating documentation and methods on the index API component
adding documentation for the index module
simplifying that last line
defaulting to `nil` index names
updating the docs to reflect the default `nil` index name
whooops! removing experimental methods
make the index name optional here
updating our facts about analyzers
making `nil` the default node_id
extracting special key handling into some constants
updating the bulk indexing special keys
updating the changelog
adding a document existence check
Making the index name optional here as well

And the `multi_get` method has been changed so that the `:type` is passed in via
the params and **not** via the request body any more.
validate the index name if it is _not_ nil
updating more documentation
adding support for termvector API calls
first whack at documenting the documents component
a few more words here will not hurt