Update Scintilla to version 3.10.4

X-Scintilla-Commit-ID: ee3fe56c6fe815781d02fbc7d55d9f15f9c439aa

Say hello to Geany 1.36 "Poliff"!

Add new upstream candidate Flex parser

Restart the shell if VTE restart is requested

Doing so drops the rectangular selection, and there is no obvious
correct behavior for line breaking with a rectangular selection.
So, just don't do line breaking in this case.

Fixes #2051.

Fixes #2066.

X-Scintilla-Commit-ID: df5c32512d3d6b71ee6138c709b392258c3a1991,
                       25a0367e9349c8475c619a054af7bf1daf15b04c
X-Scintilla-Bug-ID: https://sourceforge.net/p/scintilla/bugs/2078/

COBOL: Import new upstream candidate parser

See: https://github.com/universal-ctags/ctags/pull/2084

This import has 3 difference with upstream, not to use newer API than
current Geany has, and to workaround current limitations of Geany ctags
calls: imports are enabled by default and don't have a specific role.

Closes #2090.

* Update zh_CN.po

* Update zh_CN.po

Use `void` for empty argument lists.

This fixes support for COBOL symbols after the recent breakage of regex
parsers, as well as introducing additional features and bug fixes.

Also import some of the tests.

https://github.com/universal-ctags/ctags/pull/2076

Part of #2119.

This allows the accessibility layer to request detail, such as which
characters have been deleted.  ATK will query the deleted range to
report the data that was removed, so it must still be available for
the query to give a correct answer.
So, emit the signal in BEFOREDELETE instead of DELETETEXT.

X-Scintilla-Bug-URL: https://sourceforge.net/p/scintilla/bugs/2095/
X-Scintilla-Commit-ID: 0a937b4c0b2be02042473baed62543ff73d90807

It's quite a lot faster even after trying and optimizing the custom
version, and it makes the code simpler.

Also improve ByteOffsetFromCharacterOffset() to make use of the cache,
making it drastically faster.

X-Scintilla-Bug-URL: https://sourceforge.net/p/scintilla/bugs/2094/
X-Scintilla-Commit-ID: 01aab5f24e50ed14551c8c9c8ecce7ece0594c09
X-Scintilla-Commit-ID: 2c8b52af4ae5de2abe7c00fd18e78be60340cbf9

Fixes #2092.

Add 2 new strings

Fix loading the default open encoding option

Introduced in #2111, this gets caught by GCC's -Wformat-security which
is enabled as an error in our nightly builds.

Update all copyright notices to mention only the first publish year

And so remove the current year to ease maintenance and since it is not
strictly necessary.
Also remove individual copyright holders (where appropriate) and replace
the name with "The Geany contributors". The detailed authorship
information is still available in the GIT history.

Also remove copyright notice and author names from READMEs.

Improve IPC socket handling

SO_REUSEADDR on Windows allows to bind to an already used port
without an error. This way we never notice if the port is already used.
So use the Windows special flag SO_EXCLUSIVEADDRUSE to ensure we receive
an error if the port is already used.

Part of #641.

We need to explicitly raise the main window on IPC commands
only when opening files and similar.
For query commands like "doclist" the focus should stay on the
remote instance.