Fixes ArcticaProject/nx-libs#301, #631

Backport from xorg-xserver:

  commit ca82d4bddf235c9b68d51d68636bab40eafb9889
  Author: Eric Anholt <eric@anholt.net>
  Date:   Fri Aug 31 13:00:23 2007 -0700

    Bug #7186: Fix an excessive request size limitation that broke big-requests.

    MAXBUFSIZE appears to be a leftover of some previous time.  Instead, just
    use maxBigRequestSize when bigreqs are available (limiting buffers to ~16MB).
    When bigreqs are not available, needed won't be larger than the maximum
    size of a non-bigreqs request (256kB).

 Attributes GH PR #687: https://github.com/ArcticaProject/nx-libs/pull/687

 Reviewed by Ulrich Sibiller <uli42@gmx.de> -- Fri, 24 Aug 2018 21:47:34 +0000 (UTC)

Call checkX2goAgent much earlier (in ddxProcessArgument) and adapt NXAGENTWINDOWNAMELENGTH to its result.

Attributes GH PR #725: https://github.com/ArcticaProject/nx-libs/pull/725

Same as in nxcomp's option handling. We really only need it for ","
(%2C) and "=" (%3D), currently, but it can handle all encoded
characters.

new name is more descriptive

Attributes GH PR #724: https://github.com/ArcticaProject/nx-libs/pull/724

We do not need two versions in the code

Attributes GH PR #721: https://github.com/ArcticaProject/nx-libs/pull/721

Windowsize was wrong when run with nxagent :<someDisplay>.

Basically three changes:
- reference sizeHints and wmHints correctly (no &)
- do not use uninitialized wmHints
- set wmHints Xutf8SetWMProperties() call instead of separate call

Attributes GH PR #675: https://github.com/ArcticaProject/nx-libs/pull/675

Fixes this message when compiling with TEST:

Events.c:2725:22: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
         message_data = validateString(NameForAtom(x.u.clientMessage.u.l.longs0));

format ‘%p’ expects argument of type ‘void *’

"ISO C forbids assignment between function pointer and 'void *' [-pedantic]"

Attributes GH PR #692: https://github.com/ArcticaProject/nx-libs/pull/692

 Fixes ArcticaProject/nx-libs#691.

Attributes GH PR #718: https://github.com/ArcticaProject/nx-libs/pull/718

Attributes GH PR #705: https://github.com/ArcticaProject/nx-libs/pull/705

 Backport from X.org:

 commit 724dbc2f8bbe2f21bf16f20ca7b8bb555516626c
 Author: Alan Coopersmith <Alan.Coopersmith@sun.com>
 Date:   Tue May 2 01:30:37 2006 +0000

    Use min() [defined in include/misc.h] instead of MIN() [not defined in any
        Xorg header].
Backported-to-NX-by: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>

Backported from X.org:

  commit 491cf02e191e70c5ce24c19da880bb79bebfc03c
  Author: Jon TURNEY <jon.turney@dronecode.org.uk>
  Date:   Tue Feb 10 2015 14:37:26 +0000

    [PATCH] os: XDMCP options like -query etc. should imply -listen tcp

    In X server 1.17, the default configuration is now -nolisten tcp.  In this
    configuration, XDMCP options don't work usefully, as the X server is not
    listening on the port for the display that it tells the display manager to
    connect to.
Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>

Backported-to-NX-by: Mihai Moldovan <ionic@ionic.de

misc: fix more regressions and whitespace weirdness introduced in 913fcf1a.

 Remove one over-zealous free() call. Thanks to Ulrich Sibiller for
 spotting this.

Fixes ArcticaProject/nx-libs#704

Backport from kbproto:

  commit 2306fcd4c511d41ae4b31b9cbd9f79cf69287730
  Author: Dirk Wallenstein <halsmit@t-online.de>
  Date:   Fri Feb 5 20:42:43 2010 +0100

      Use the correct value for XkbAllAccessXEventsMask
Signed-off-by: Dirk Wallenstein <halsmit@t-online.de>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Backported-to-NX-by: Ulrich Sibiller <uli42@gmx.de>

Attributes GH PR #678: https://github.com/ArcticaProject/nx-libs/pull/678

Attributes GH PR #709: https://github.com/ArcticaProject/nx-libs/pull/709

Fixes: ArcticaProject/nx-libs#708

Attributes GH PR #706: https://github.com/ArcticaProject/nx-libs/pull/706