Add batch plotting code for iterations plots

Still need to test this on Minerva and add threshold plotting functionality
Handle case where no results are found
Header line is now skipped in results files
Clean up plots a little
use pyplot.plot instead of pyplot.errorbar
Use ymax instead of ymin

Need more coffee...
let mpl choose legend location
Add initial threshold plotting code

Still needs testing on Minerva
Fix indent
Add missing import
use linestyle instead of marker
Add more stringent checking of dirs to process

Could hit a case where .tmp dirs were being processed, which we never want to happen.
Merge pull request #33 from rybern/refactoring

Refactored, added errors/asserts
Merge pull request #35 from rybern/refactoring

Fixed KeyError, addressed speed problems
Merge pull request #36 from rybern/refactoring

Removed reference to old function, fixed issue where None values were ge...
Add tests for ProcessDefinition
Add remaining tests for parallel_processing module
Fix a typo and remove debug line
Add tests for parse module

Also add stricter error checking / requirements of the input file formats.
Add tests for utils module

Also add more extensive error checking/handling.