Pythutils

* Improved listfiles function's use of parameters

* Fixed picamconv to have horizontal blocks of 16 pixels
* Fixed name function throwing an error when working with directories

* Improved error checking by changing asserts to raising exceptions
* Added fourpt_transform function to get a top-down view of a cropped
section of an image
* Added sort_points function to sort points from tl to bl

* Further generalised and improved mouse_events class
* Added a function to fix the coordinates of two-point to be from LT to BR
* Fixed draw_sliced_line function
* Added draw_hcross function
* Added helper class to view dictionary as an object
* Fixed get_ext function for non-string input
* Improved check_media function to work with streams
* Added simple midpoint function
* Added pandas query function

* Improved logger class for easier starting and stopping of logging across
systems
* Enabled sameline printing in lineprint function
* Fixed varname in seqcount function

* Added get_spaced_colors function for getting a list of equally spaced
colors on the color spectrum
* Added function to draw bi-coloured circles of increasing size on an image
* Added function to draw a dotted or dashed line on an image
* Added function to draw a semi-transparent polyline with decreasing
width on an image
* Added function to convert opencv contour object to tuple