Fix default size, horizontal and vertical precition values for LOC records.

Default values in RFC 1876 are in meters but the old code used
the numerical value as centimeters.
Fix vertical precision parsing for LOC records.

Vertical precision value was ignored if the optional 'm' (unit)
was missing at the end of input and rest of the input was ignored.
Allows to copy dns.name.Name objects
Pull up 42a85bfb058e6d59b7674651c6fba3aebd8a3481 from dnspython.
add options rotate handling

for resolv.conf "options rotate" line, enable shuffling of nameservers
before each query. (should just rotate start position and maintain order?).
Pull up fcde73a2b6c323e55eaf74192885b2d4922a719a from dnspython.
Tweak options rotate.
Add dns.zone.to_text() convenience method.
pull up unicode escaping changes.
Fix some issues with dns.zone.to_file().
Fix exception when reading from a masterfile.
Fix relativization in RRSIG to_text().
Allow empty APL RR.
Add dns.rdtypes.ANY.DNSKEY.flags_to_text_set() and flags_from_text_set().

Map between DNSKEY RR flags bit array and set of human-readable names.
Fix test_rdtypeanydnskey.py for python3.
Fix python3 port problem.
Add dns.ipv6.is_mapped(); Reverse IPv6 mapped IPv4 into v4 space.
Overhaul test suite to allow testing in place.
Update ChangeLog.
Prep 1.12.0