Began to add lexicalisation code.

Created a new subpackage: provglish.lexicalisation, along with associated test
package.

Currently only one method implemented: provglish.lexicalisation.urn_from_uri()
	  This method takes a string, or object that can be cast to a string
	  and returns everything after the last # or / (whichever comes last).
Removed test.py

It should never have been committed. Whoops.
Added provglish.lexicalisation.plural_p and associated tests

Takes a string (assumes a single word...) and if it's a plural noun,
returns True, else returns False. That's the idea, anyway.
Added a function provglish.prov.fetch_all_prov_things and tests

This returns a list of URIs for every prov:Entity, prov:Collection, prov:Agent
or prov:Activity in the graph.
Updated the setup.py and .travis.yml file to reflect nltk dependency

The .travis.yml file now downloads all of the NLTK features. This is likely
to be time/bandwidth intensive for Travis. Not sure if they're going to like
it a whole lot. It might be necessary to pare it down to just the essentials.
Fixed setup.py

Removed the brackets around part of one of the strings, which was causing
pip to fail on the CI server.
Changed the plural_p regular expression

Given that the only values that we should be accepting are NNS and NNPS,
I changed the RE to "NNP?S" rather than "NN.*S", which was far less
precise.
Moved the nltk.downloader.download("all") command into the setup.py script

This way it should be set up when the module is installed, rather than afterwards.
Added provglish.prov.fetch_related_alternates(graph, uri) function

This function takes a URI (casts to URIRef, so works with a string.) and
returns a tuple containing all the related entities in the prov_graph graph.

It will also return the URI itself, even if the URI is not in the prov_graph.
Added an exception prov.QueriesNotInitedError

This exception is to be raised whenever a query function is called, but the
prov.query_init() function has not been called. This is because it was hurting
my brain every time I saw a KeyError when I knew the key was correct. This error
is far easier to understand.
Changed the auto-download on install of nltk packages

Instead of downloading "all", it now only downloads the pos tagging
package called "maxent_treebank_pos_tagger".
Added prov.fetch_all_agents(graph) query.

Returns the URIs of all the instances of prov:Agent in the graph prov_graph.
Added a test for str(prov.QueriesNotInitedError)

Just because it was annoying me that it was pulling down coverage.
Added \#*\# to .gitignore

This is so that it doesn't try and deal with emacs backup files.
Added prov.fetch_associated_activities and related tests

This function returns all the activities associated with the given agent.
Added .\# to .gitignore

It turns out emacs has even more tempory file name conventions...
Added prov.fetch_entities_derived_by_activity(graph, activity) and tests

This function returns any entity in graph for which there is a qualified
derivation with the property hadActivity equal to activity.