Fix corner ordering in documentation

[garydoranjr]

The following documentation is incorrect:

pdsc/pdsc/localization.py

Lines 368 to 375 in 74893bb

	:param corners:
	an ordered collection of the four image corners, each a latitude and
	east longitude pair (in degrees); the order of the corners is:
	- top left
	- bottom left
	- bottom right
	- top right

Instead, the expected ordering of the corners is:

• top left
• top right
• bottom right
• bottom left