Skip tests on python implementations without getrefcount()

PyPy is one of these.
Added test to verify copysize handling in copy_expert

Not an original psycopg2 bug but present in pure python implementation,
e.g. ctypes issue #25 and cffi issue #5.

https://github.com/mvantellingen/psycopg2-ctypes/issues/25
https://github.com/chtd/psycopg2cffi/pull/5
Added regression test for infinity parsing in dates

...and a couple of typos.
more useful error message when comparing ranges with non-ranges
raising an exception here rather than returning False causes problems with SQLAlchemy's internal state tracking
cater for comparison of subclasses
Uniform Range eq tests style
Mention the Range eq fix in the NEWS file
Merge branch 'range_eq_typerror'
Added doc example to convert date.max to infinity

See issue #163.
Untrack the connection before closing to avoid possible double-free

From Gangadharan S.A. Fixes issue #166.
Fixed doc index entry for infinite dates
Fixed titles in newsfile

The first title at the same level of the main releases helps getting a
more regular ToC in the docs main page.
Fixed pickling of exceptions with no pgerror/pgcode set

Fixes ticket #170.
Meaningful connection errors report a meaningful message

Fixes issue #173.
Document that using %, (, ) in the placeholder name is not supported
Document that named cursors don't raise an exception going out-of-bound

See issue #174 for the details.
Really test named cursors in test_scroll_named()
Use bytestrings in infinite dates adapter example

Returning strings would result in unclear tracebacks on Py3 (see ticket #163).
Typo fixes and improvements to new_array_type() docs