IMAPX: Remove unused CAMEL_IMAPX_COMMAND_STREAM option.

99% sure this is unused.  Or at least can't find any cases of "%S" in
CamelIMAPXCommand format strings.
Add CamelNullOutputStream.

GOutputStream subclass to eventually replace CamelStreamNull.
maildir_store_get_folder_sync: Fix a use-after-free issue
Updated Traditional Chinese translation(Hong Kong and Taiwan)
Bug 719583 - Get a ESourceRegistry singleton
Update API documentation.
NEWS update for 3.11.5 release.
Post-release version bump.
updated kn.po
Bug 723481 - Wrong callback signature in imapx_process_read_to_read()

Didn't realize UNIX file descriptor GSources use a special callback
signature.  Could be better documented in g_unix_fd_source_new().
Bug #720676 - [IMAPX] Do more searching server-side (take ][)

The first patch caused server-side searching also for cases where all
data were available locally, which made searching slower. This tests
first if everything in match-all is available locally, and if so, then
it uses local search, rather than the server side.
Simplify imapx_query_auth_types_sync().

A new CamelIMAPXServer instance is not connected, so no need to
check for it.  Must be leftover logic from CamelIMAPXConnManager.
imapx_query_auth_types_sync: Remove offline check.

Let the operation fail naturally when the IMAP server isn't reachable.
Bug #721030 - WebDAV: download_contacts() leaks
ESource changes not always written to a disk

This is a regression after my commit 294ec486b3bcb82192844fba07a642a789d19e25,
but if you look few lines above, how the save-to-disk works, then it's obvious
that this could easily break. The actual problem here was that if there didn't
change any of loaded extensions, then the source didn't change, due to avoided
test of changes on unloaded extensions, which wasn't a problem before the above
cited commit, because the code relied on false 'changed' notifications.
Bug #720940 - Always asked to synchronize folders when going offline
Add camel_mime_parser_init_with_input_stream().

Similar to camel_mime_parser_init_with_stream(), but takes a
GInputStream instead of a CamelStream.
Reimplement camel_mime_parser_init_with_fd().

Now creates a GUnixInputStream and hands it off to
camel_mime_parser_init_with_input_stream().

Removed functions:

  camel_mime_parser_fd()
imapx_call_idle: Do not print Cancelled errors on console
Bug #720751 - camel_tag_set() doesn't copy tag's name properly