Fix tests for TimeStream

* tests/test_classes.py (test_read_metatdata_weird): We now raise an Attribute
error.
(test_timestream_init_bad_params): To trigger the exception we need to pass an
actuall string. "" is as if we didn't pass anything
(test_iter_by_timepoints_withgaps_no_rm_gaps): This no longer returns a None
image. Now we check to see if pixels is of length zero.
* timestream/__init__.py (TimeStream.__init__): We assing version to
self.version effectively running the necessary checks.
Initial commit for the derandomization GUI

We begin with a setup that has the basics for image zoom/pan and a visualization
of the csv file. We also have two buttons that add images and csv files.
* util/derandui.py (DerandomizeGUI): New class that will hold all logic for the
derandomization gui.
(PanZoomGraphicsView): New class for visualizing images with pan and zoom.
* util/derandui.ui: This is the skeleton of the GUI. File produced by "designer"
(Qt's gui designer).
Add time stream list.

* util/derandui.py: Add GPL text.
(timeStreams): Dictionary that holds all the opened timestreams.
(onClickTimeStreamList): When we click on the "+" symbol we add a timestream
directory. We fail with an error message is TimeStream.load fails.
* util/derandui.ui: We add the timestream list as a TableWidget to the user
interface. We add a hidden colomn to relate the rows in the timestream list to
the new self.timeStreams dictionary.
Remove frame margin.

* util/derandui.ui: So we can give more space for the timestream list, image and
csv table.
Open TimeStreamTraverser and show an image

* timestream/__init__.py (TimeStreamTraverser): New class that inherits from
TimeStream. It implements the timestream as a backwards and forwards moving
object. The rest is basically the same as TimeStream.
(TimeStreamTraverser.{next,prev,curr}): New methods for new class. They are
responsable for keeping internal track of where the timestreamtraverser is. If
we overflow we continue at end or start of time stream.
* util/derandui.py (showImage): Puts an image on the scene.
(selectFile): Removed this method.
Install matplotlib & numpy in travisCI
apt-get install things if we can in travis CI
[travis.yml] Add scipy to pip installs
another vain attempt to fix travis

Install BLAS lib & gfortran to try fixing pip install scipy
Be less verbose in install in travis CI
Fix visualisation for experimenmts without pot location