* There are patches on top of Scintilla as were before
* Scinterm has been switched back to the upstream repository and there are unreleased
  commits - especially for out-of-tree builds.
* Lexilla hasn't been released since my troff lexer was merged.

* You no longer have to copy contrib/scintilla, contrib/scinterm and contrib/lexilla
  manually to the build directory.
* It turns out, that Scintilla/Lexilla was supporting this since 2016.
  Scintilla allows pointing to a source directory (srdir) and Lexilla to a binary directory (DIR_O).
* For Scinterm I opened a pull request in order to add srcdir/basedir variables:
  https://github.com/orbitalquark/scinterm/pull/21
* `make distcheck` is therefore now also fixed.
* The FreeBSD package is now allowed to build out of source.
  I haven't tested it yet.
* See also https://github.com/ScintillaOrg/lexilla/issues/266

This should not change anything functionally.

* The patch for indicator styles turned out to be unnecessary,
  so I switched back to the mainline Scinterm repository.
* Scinterm is now on the latest commit that still supports my version of Scintilla (v5.3.4).

* The scinterm submodule temporarily points to my own fork.
* This is necessary for the aspell macro on Curses.
  See https://github.com/rhaberkorn/sciteco/wiki/Useful-Macros#spell-checker
* See also https://github.com/orbitalquark/scinterm/pull/19

* This is optimized for Groff, but works for Heirloom Troff and Neatroff as well.
  Currently, the Heirloom and Neatroff requests are just added ontop of the Groff
  ones. Theoretically, we could also try to separate the keyword lists into
  a base K&R set with Groff, Heirloom and Neatroff ontop.
* The lexer necessarily has many restrictions, as Troff is fundamentally unparseable
  (like classic TECO) and needs a lot of per-request knowledge.
* The "*.mm" extension has been removed from the lexers/cpp.tes.
  I don't know what language this was for, and I prefer `*.mm` files
  to be considered Troff.
* Temporarily changed the lexilla submodule URL.
  The corresponding Lexila lexer is in the process of being upstreamed.
  Once it is, I will probably revert the submodule to the official repository,
  as the "troff" branch is not stable (can be rebased).

* Turns out that using gtk_widget_destroy(), the finalize handler never gets called!?
  This means we were leaking memory.
* Using g_object_unref() fixes that and the initial Scintilla patch is no longer necessary.
* There have previously been use-after-free bugs when *not* using gtk_widget_destroy().
  This has apparently been fixed in the meantime in Scintilla.

* the GObject lifecycle was violated, resulting in use-after-free scenarios