Added one test for a request with matching UIDVALIDITY and one which is
a mismatched request that will fail.

Any IMAP parameter can come in escaped and in double quotes. Added a
simple function to unquote the command parameters and applied it to
the IMAP command handlers.

The whole of FETCH_imap() had one extra space of indentation, whilst
APPEND_imap() used indentation of 2 instead of 4 in places.

The majority of lines, that specify a test file for inclusion, end with
a tab character before the slash whilst some end with a space. Corrected
those that end with a space to end with a tab character as well.

Finished segregating the email protocol tests, into their own protocol
based ranges, in preparation of adding more e-mail related tests to the
test suite.

Continued segregating the email protocol tests, into their own protocol
based ranges, in preparation of adding more e-mail related tests to the
test suite.

Continued segregating the email protocol tests, into their own protocol
based ranges, in preparation of adding more e-mail related tests to the
test suite.

Started segregating the email protocol tests, into their own protocol
based ranges, in preparation of adding more e-mail related tests to the
test suite.

Patch by: Myk Taylor

... hopefully this will also make clang-analyzer stop warning on
potentional NULL dereferences (which were false positives anyway).

When Curl_do() returns failure, the connection pointer could be NULL so
the code path following needs to that that into account.

Bug: http://curl.haxx.se/mail/lib-2013-03/0062.html
Reported by: Eric Hu

Standardised the naming of all perform based functions to be in the form
imap_perform_something().

No more use exit(3) but instead tell libcurl that no byte has been
written to let it return a `CURLE_WRITE_ERROR`. In addition, check
curl easy handle return code.

8 more bugfixes, one change and a bunch of contributors

Moved the custom request processing into the LIST command as the logic
is the same.

Updated the function description comments following commit 4838d196.

Moved the blocking state machine to the disconnect functions so that the
logout / quit functions are only responsible for sending the actual
command needed to logout or quit.

Additionally removed the hard return on failure.

Added comments and simplified convoluted dophase_done comparison.

Added an exception, for the STORE command, to the untagged response
processor in imap_endofresp() as servers will back respones containing
the FETCH keyword instead.

GCC specific adjustments:

- check __ILP32__ before 32 and 64bit processor architectures in
  order to detect ILP32 programming model on 64 bit processors
  which, of course, also support LP64 programming model, when using
  gcc 4.7 or newer.

- keep 32bit processor architecture checks in order to support gcc
  versions older than 4.7 which don't define __ILP32__

- check __LP64__ for gcc 3.3 and newer, while keeping 64bit processor
  architecture checks for older versions which don't define __LP64__

Bug: http://curl.haxx.se/bug/view.cgi?id=1205
Reported by: technion

Removed unwanted braces and added variable initialisation.