* Many unused import cleanups
Ignored some star imports, some vendored code in colorama, only looked within pyqtgraph the library, not e.g. examples
* SpinBox decimal imported with both import and from import
Significant performance issues have been identified with np.clip
and thus clip_array was created to speed up the operation. In addition
clip_scalar was created to clip a scalar value between two other values
this commit replaces many uses of np.clip from operating on scalars to
using clip_scalar instead
* py3k: Remove reduce calls.
* py3k: Remove compatibility sortList function.
Sorting by key has existed since Python 2.4.
* Remove unnecessary sys.path manipulation.
This file doesn't have any __main__ code to run anyway.
* Use context manager
Fixes#103. If a ScatterPlotItem was removed from a plot and added
again, glGenTetures was called again unneccesarily. Each time it is
called, it eats up a little more space.
Kyle Sunden
Ogi Moore
Kenneth Lyons
Aikhjarto
2xB
Fekete Imre
John David Reaver
Luke Campagnola
tommy3001
Guillaume Poulin