Start copy constructor, specifically Circles

PHYS-16 #time 40m
Maybe have some version of Circle copy working

PHYS-16 #time 25m

I'm using a non-const version right now, which should probably be
changed sooner rather than later, and I'm not 100% certain it's working
properly, but it's at least compiling. Battery is running low, so I have
to commit sooner than I would like.
Delete inappropriate websites directory
Merge branch 'nightly' of github.com:swoogles/Physics into nightly