sync from upstream up to 22:14a375563e2b

This includes the following commits:

changeset:   22:14a375563e2b
summary:     chang "while" command to "type -P" in bash based configure

changeset:   21:c4bf7c0f33d2
summary:     updated codec paper for RS01 life cycle

changeset:   20:dbcaad8128aa
summary:     replaced build count with mercurial changeset

changeset:   19:fba258a6acfa
summary:     Added tag 0.79.10 for changeset 49950be5a2ef

changeset:   18:49950be5a2ef
summary:     merged some debian patches

changeset:   17:815be3929c41
summary:     merged "easy" patches from Stéphane Lesimple's version

changeset:   16:7d15f8a958cb
summary:     Made printf format strings 32/64bit safe as suggested by Stéphane;

changeset:   15:1055a53b8d6d
summary:     reorganized code for --with-gui=[yes|no] option

changeset:   14:fbe2ae12a32c
summary:     Added tag 0.79.9 for changeset f2fdd6d3a1f5

changeset:   13:f2fdd6d3a1f5
summary:     updated TODO and CHANGELOG

And other changes that were needed to resolve the (many) conflicts.

TODO

@@ -2,18 +2,21 @@
 Tentative to do/ release schedule
 
 Versions 0.79.x: development releases
-* restart project, catch up wich recent compiler and OS version,
+* restart project, catch up wich recent compiler and OS version
 * last releases with gtk-2 
 
 work in progress (this release):
 
-- clean build for gcc-10 (Slackware 15, Debian testing)
+- split GUI code from core source to allow for command-line only build (done)
+- merge patches from St<53>phane Lesimple (done) and Debian (done)
 
-upcoming (next releases):
+upcoming (next stable release):
 
-- split GUI code from core source to allow for command-line only build
 - restore adaptive reading for all codecs
 
+(no more releases for 0.79.x planned;
+ except for maintenance issues should the need arise)
+
 Versions 0.80.x: development releases
 * gtk-4 migration
 * lots of micro releases to revive the project and resolve outstanding issues
@@ -22,14 +25,14 @@ Versions 0.80.x: development releases
 - remove obsolete features, especially from the GUI
 - ... many more will likely be added ...
 
-Version 0.82: next milestone/stable release
+Version 0.82: milestone/stable release
  - RS03 encoding considered feature complete
 
 Version 0.83: development releases
  - multithreaded decoding (error correction/repair) 
    for RS01/RS02/RS03
 
-Version 0.84: milestone release
+Version 0.84: milestone/stable release
  - RS03 decoding considered feature complete
 
 Version 0.90: