temporarily use EPNP in SolvePnP instead of UPNP or DLS algorithms, since the latter two are not quite stable

Trying to fix whitespace issue.
This reverts commit dcc2512f.

added a check to prevent illegal access to operator[] when vector is empty

Removed check on limits.  A common use of HoughLines would be to restrict theta to be between a small negative number and a small positive number, e.g. -pi/16 to pi/16.  This wasn't possible with the previous checks.

made the solvepnp a bit more modest; test 5-point configuration instead of 4-point in some cases; reduce the noise in 4-point configurations in other cases

REG_NONE defined in ml.hpp conflicts with defined in Winnt.h

Incorrect number of input arguments in main function

Previously the Python3 cv2 package ends up with no submodules (bgsegm, face,
etc) in it, which makes a lot of functionality unusable. By not writing over
our root reference we ensure the new submodules are added to the correct cv2
module.