Remove specifics from configuration.py

* timestream/manipulate/configuration.py (PCFGConfig.__init__): Use the
underscore "_" for internal variables so we can have subsections named
"configFile" and "depth".
(PCFGConfig.loadFromYaml): Configuration is just a structure that holds whatever
is on the path that it is handed. It reflects what is in a config file or what
is added through the methods. We should not add stuff that the caller does not
know about.
* util/pipeline_demo.py (plConf): We can add the confFile subsection after we
create plConf and it should have the same result.
Use the __str__ method from TimeStream.

* util/pipeline_demo.py (ts): print(ts) should print all relative information.
Remove unnecessary comments

* util/pipeline_demo.py: Remove all comments regarding previous context
variable.
Add selectRowTS to derandomize GUI.

Change the pixmap every time a timestream is selected in the ts list.
Also changed the internal variables in DerandomizeGUI to be prefixed by "_"
* util/derandui.py (selectRowTS): New method. Does the timestream selection and
takes care of the row coloring.
* util/derandui.ui: Make sure that the elements in the timestream table are not
selectable.
Populate first column when adding a timestream

* timestream/manipulate/pot.py(numPots): New property that returns the number of
pots in a ImagePotMatrix.
* util/derandui.py (WindowTS): New class that contains the relation between
TimeStreamTraverser instance and the csv table. Its easier to have them together
as they change at the same time in the GUI.
(onClickTimeStreamList): Check to see if TimeStreamTraverser has all relevant
information before we add to list. We use the new WindowTS here. Ignore clicks
to the last row in the tslist.
(selectRowTS): Incorporate ddm in when selecting row in tslist.
(DropDownMenu, DropDownMenu_TS): New classes that contain menu widget for csv
table headers. They will contain all logic that has to do with filling the
column under the header.
* util/derandui.ui: Initialize the csv with 2 columns and one row, No headers.
Replace DropDownMenu with QComboBox

* util/derandui.py (QComboBox_TS): New class replacing DropDownMenu and friends.
(DropDownMenu, DropDownMenu_TS): Removed Classes
Change first column when metaid are selected

* util/derandui.py (onChange): New Method that will change the first column on
metaid selection.
Clean the first column when add/removing timestreams

* util/derandui.py (onClickTimeStreamList): We clean all the first column if we
end up with a _activeTS == None
(onChange): Ignore the signal if we have no self._tst
Remove _timestreams

We keep track with the qtlist.
* util/derandui.py: Store the TimeStreamTraverser in list item data.
* util/derandui.ui: Remove the hidden column.
Adjust the csv upload logic.

* util/derandui.py (selectCsv): It now fills the csv data from the second column
on.
Fix visualisation for experimenmts without pot location
Quick fix to read timestream without fixed time interval.
Need better solution to deal with this situation.
Add color parameter estimation using white background.
This is used when there is no color card or color card info
is contaminated due to shadow or other things.