Python Driver v1.12.0-1
Reformatted a comment.
Made blob::traverse_helper_t::preprocess return a buf_lock_t because C++11.
Added an integer-interval pmap function.
Replaced for loop traverse_index call with a pmap.
Removed the unused pimap function, simplified other pmap code.
Fix for #1811 , might be improved.
More fixes for #1811.
Do not have more than one outstanding CONTINUE request
Python driver 1.12.0-2
Merge commit '53e23c7' into HEAD

Conflicts:
	drivers/python/setup.py
Removed version numbers from serialization macros.
Removed some manually implemented serializer version information.
Remove some more manual implementations of serializer version numbers.
Removed versioning from seemingly the rest of the manually versioned serializers.
Removed VERSION_ERROR and manual wire_func_t serialization versioning.
Fixed a trailing whitespace line.
Made helper type mailbox_header_t.
Some irrelevant comment/whitespace/casting cleanup.
Added helper methods and types for comparing and manipulating clustner version numbers.