Add GUI display for BaxterObject.

This makes it easier to evaluate results without having to consult
outputted images in the file directory.
Add directory import method.
Reorganize import and rename BaxterObjectView.

BaxterObjectView has been renamed to BaxterExperiment, to reflect its
purpose of providing an easy interface with other modules to carry out
image segmentation. The mass import_images() method was moved over to
BaxterExperiment accordingly.
Add command line parser.

The Baxter algorithm will be able to use BaxterExperiment by itself, but
this allows for more convenient post-hoc analysis.
Fix command-line parsing bugs.
Adjust slider values.

An extra unnecessary tick was removed.
Fix export results method.

Some variables were misnamed.
Clean up code.

Unnecessary comments were removed.
Merge pull request #8 from vancezuo/gui

Gui branch merge.