setup.py used for PyPI distribution of conduit v0.0.2.
Added mechanism for creating documentation via sphinx ( http://sphinx-doc.org ).
To build docs, go to the "doc" subdirectory and run:
make html
Added GeneratorBlock class as a simple mechanism for users to wrap python generator functions
inside a dataflow block.
See example in conduit/examples/generator_example.py
Added code to generator example (and fixed an accompanying bug) to allow a generator block
to provide output to downstream blocks.
Added test for ">>" syntax, which also serves as an example for using a GeneratorBlock.
Fixed CTT-361: Remove comparison of autogenerated timestamps with user generated timestamps.

Modified .gitignore so that it ignores the _build directory, which contains sphinx-doc outputs.
Provided implementation and test for CTT-365: Allow specification of start and end dates
Bump version to 0.0.3 for pip.
Added the ability to provide a subset of the required outputs in a given iteration.
In the test added for this, a generator block has two outputs. On the first iteration
it fills one of its output channels, while the information in the other output channel
is updated on all subsequent iterations (see test_partial_outputs).
Added new test for blocks which provide output on different channels for different iterations.
Added "time" as a field in the channel class, rather than just assuming that channel time is identical
to the time of the data it holds (channel time can advance while the data stays the same).
Added lists of "visited blocks" to the tests.
* Additional tests
* Fixed bug that arises in certain graph topologies when the blocks provide only a subset of the possible
  outputs on a given iteration.
* Updated setup.py to obtain its "long_description" from README.md.
* Added CHANGELOG.
* Added dev_requirements.txt (use 'pip install -r dev_requirements.txt' if you wish to have Conduit installed
  along with its requirements for developers (e.g. the nose testing framework)
Fixed pip installer so that it can find README.md.
Modified execution engine such that blocks are guaranteed to be called in topologically sorted order.
This fixes an intermittent bug that occasionally showed up in graphs that had blocks whose inputs took
turns providing data at alternating timesteps.
Added a trace mechanism which obviates the need for a global variable to aggregate a list of "visited blocks".
Updated CHANGELOG and setup.py for release 0.0.7
Fix for a problem in which _get_all_input_values() was looking for data in all channels,
as opposed to all values pulled from the channels.