Replace Point class with a 3 position tuple and a collection of helper functions.

PyCam has been spending about 75% of it's time creating point objects. I decided to replace
the pycam Point object with a 3 position tuple, and the pycam Vector object with a 4 position tuple.

All of the point object methods were rewritten to accept and emit tuples. The transform_by_matrix method
was rewritten to accept both 3 and 4 position tuples with behavior dependent on that size. The
normalized method is the only method required to emit the same kind of object that it is called on, and
this has been taken care of with the tuple version.

What does this mean?
All instances of Point(x,y,z) have been converted into (x,y,z)
All instances of Vector(x,y,z) have been converted into (x,y,z,'v')
The notation to access the x,y,z of the Point objects has been been changed
	from p.x,p.y,p.z to p[0],p[1],p[2]
The notation for the point math functions has been completely changed.
Instead of p1.sub(p2) it has been converted to psub(p1,p2)
Instead of p1.sub(p2).mul(0.5) it has been converted to pmul(psub(p1,p2), 0.5)

It is very important to point out that the tuple is an immutable type.
You can not change it once you create it.
t[0] = calculated_x_value # syntax error
You have to replace the reference (t) to the old tuple with a new reference to a new tuple.
t = (calculated_x_value, t[1], t[2]) # works

There was a particularly hairy mutable/immutable barrier in the next() generator present in each class that
inherits TransformableContainer. The TransformableContainer.transform_by_matrix function uses these
generators to collapse polygons and lines and triangles into points where a shift is performed on each.
Now that point is immutable, you can not change the value emitted by the generator.
Geometry/__init__.py transform_by_marix and the associated next() generator in each sub class has been
rewritten to transfer the attr used to store the reference to the tuple.
Geometry/__init__.py transform_by_matrix now sets these attributes which effectively gets around this
limitation.

There could be some old point object code in any of the files not contained in this commit.
It is impossible to know without running the code path and/or careful analysis of each file.

Some list comprehensions that convert a list of point objects into a 3 position tuple have been removed.

Whitham D. Reeve II
Fixed another casualty of the switch from point objects to point tuples.
Fixed a sluggish opengl window when a tool path is displayed.

Profiler suggests that the min/max functions for x/y/z of the Toolpath object were the main bottleneck. They iterate through all the points in each path every time they are accessed. These values are now cached which provides a huge speed boost. Originally I thought the problem was the opengl drawing code so I created a new code path that converts moves into an arrays of vertices and indices. The vertices array particularly is stored in video memory. While faster, I don't think it is all that much faster.

Whitham D. Reeve II
Fixed yet another casualty of the move from Point object to point tuple.
Direction cone speed improvements.

This code commits draw_direction_cone_mesh which is an adaptation of draw_direction_cone to generate a mesh of triangles for compression inside a vertex buffer object. The rest of the opengl code in Toolpath has been changed to use this. Only remaining use of old rendering path way is simulation.

Whitham D. Reeve II
Some efficiency toolpath rendering pathway efficiency improvements

Made changes to remove consecutive duplicate points, combined two loops that iterated through points into one.
Fixed problem in font preview caused by move from point object to point tuple.
Minor tuple conversion change.
Code cleanup.
Fixed bug that affects closed polylines.

Original developer left out a condition in a trailing else to generate an additional line to close a polyline when specified.
Another fix having to do with the move from point object to point tuple.
Fixed a floating point issue that caused a zero length line in a polygon simplification algorithm.
Removed old commented out code and converted PolygonExtractor.py to new Point tuple style.
Remove old commented out code.
Remove old commented out code.
Remove old commented out code.
Removed old commented out code
Remove old commented out code.
Remove old commented out code.
Removed old commented out code.