Readme updated

Forgot to add documentation for `show_uri`
Fix sector chart if only one set to draw

SVG arc cannot apparently be used to draw a full circle. Check if
drawing from 0 to 360, i.e. a circle, and use .circle() instead of
.path()
Use MemoryStore in test environment

Using MongoStore in test environment halts the execution, apparently
because it is not closing. Thus use MemoryStore in test environment.
Better test framework for server tests

Use mocha and supertest to test server. We now have two kinds of tests,
nodeunit for test/test-* and mocha for test/*-test.coffee
Added a couple of server tests
Deleted unused file
Test set filters updated
Return flat list of all possible testset selections

Going to change filtering to non-restrictive - previous filtering
allowed selecting a release and a product, and test sets were displayed
by those selections. Now going to make all keys (release, profile,
testset, product) as separate filters and the possible test sets are
listed based on these ('Any' will be a supported value for each of the
fields)
Renamed hwproduct -> product. Needs work still.
Filter list of possible testsets

Users can now filter the data more flexibly by choosing to filter only
by e.g. profile. Suggestions are not yet updated.
Flexible filtering implemented

Now filtering options in left column in edit mode do not restrict the
values that can be selected offering greater flexibility in creating
widgets.

Now user can, if he wishes, show reports from e.g. different releases in
the same widget (earlier only one widget could be selected). Due to this
the title for each item in the widget now includes the whole
release/profile/testset/product combo because otherwise it would be
impossible to know what the partial part of the widget is showing.

Things to do still include:
- Widget title
- Default config
Default config fixed

Now default config is set properly for new widgets, including the title.
The default config methods for each widget were quite similar so now
creating the most of it in QAReportsWidget.