Make chart installable

[adampbeardsley]

I've done a number of things here to organize the source code.

• Removed a ton of the gnuradio templating stuff we don't actually use
• pulled our top block out of collect into a an installable module (chart.blocks)
• Moved the metadata time stamping block into the same module.
• Moved the bit of gps code into chart.gps with intention of adding more code later
• Created a setup.py file so you can install with python setup.py install
• collect.py now gets installed with the above command, so you can call it from anywhere (maybe we should rename it?)

Some things left to do (either for this PR or make an issue so we do it later):

• [x] clean up/move some of our analysis code (e.g. make chart.analysis with useful functions)
• [x] rename collect.py script to be more descriptive
• [x] Update the README with installation instructions
• [x] Tag a previous commit so we can easily reference if we want to bring the gnuradio template stuff back

closes #6, #7, #9

[lmberkhout]

Otherwise I think it looks okay

[lmberkhout]

I'm not sure how making packages works so hopefully I haven't missed something

[adampbeardsley]

@lmberkhout I think we've got everything addressed here. Steven helped me get it so you can install the analysis stuff even if you don't have gnuradio installed. Could you give it another look and approve/merge if you think it's ready?