authors: update the authors list.

Adding names of people with significant contributions:
- Jacob Boerema for his awesome work (on too much stuff to list it all!)
- Daniel Novomesky (HEIF, AVIF support)
- Félix Piédallu (meson build)
- Elad Shahar (Python 3 plug-ins, Spyrogimp, Mandala symmetry
  kaleidoscope mode)

AUTHORS

@@ -31,6 +31,7 @@ The following people have contributed code to GIMP:
  Marc Bless
  Edward Blevins
  Reagan Blundell
+ Jacob Boerema
  Hendrik Boom
  Xavier Bouchoux
  Richard Bowers
@@ -221,6 +222,7 @@ The following people have contributed code to GIMP:
  Jon Nordby
  Martin Nordholts
  Stephen Robert Norris
+ Daniel Novomesky
  Erik Nygren
  Miles O'Neal
  David Odin
@@ -238,6 +240,7 @@ The following people have contributed code to GIMP:
  Ville Pätsi
  Akkana Peck
  Asbjorn Pettersen
+ Félix Piédallu
  Mike Phillips
  Nils Philippsen
  Ari Pollak
@@ -271,6 +274,7 @@ The following people have contributed code to GIMP:
  Michael Schumacher
  Tracy Scott
  Craig Setera
+ Elad Shahar
  shark0r
  Peter Sikking
  RyōTa SimaMoto

authors.xml

@@ -33,6 +33,7 @@
   <contributor role="author" last-active="1.0">Marc Bless</contributor>
   <contributor role="author" last-active="1.0">Edward Blevins</contributor>
   <contributor role="author" last-active="1.0">Reagan Blundell</contributor>
+  <contributor role="author" last-active="2.10">Jacob Boerema</contributor>
   <contributor role="author" last-active="2.8">Hendrik Boom</contributor>
   <contributor role="author" last-active="1.0">Xavier Bouchoux</contributor>
   <contributor role="author" last-active="2.8">Richard Bowers</contributor>
@@ -240,6 +241,7 @@
   <contributor role="author" last-active="2.8">Jon Nordby</contributor>
   <contributor role="author" last-active="2.8">Martin Nordholts</contributor>
   <contributor role="author" last-active="1.0">Stephen Robert Norris</contributor>
+  <contributor role="author" last-active="2.10">Daniel Novomesky</contributor>
   <contributor role="author" last-active="1.0">Erik Nygren</contributor>
   <contributor role="author" last-active="1.0">Miles O'Neal</contributor>
   <contributor role="author" last-active="2.8">David Odin</contributor>
@@ -258,6 +260,7 @@
   <contributor role="author" last-active="2.8">Akkana Peck</contributor>
   <contributor role="documenter" last-active="2.6">Pierre Perrier</contributor>
   <contributor role="author" last-active="2.0">Asbjorn Pettersen</contributor>
+  <contributor role="author" last-active="2.10">Félix Piédallu</contributor>
   <contributor role="author" last-active="1.2">Mike Phillips</contributor>
   <contributor role="author" last-active="2.8">Nils Philippsen</contributor>
   <contributor role="author" last-active="2.4">Ari Pollak</contributor>
@@ -293,6 +296,7 @@
   <contributor role="author" last-active="2.8">Michael Schumacher</contributor>
   <contributor role="author" last-active="1.0">Tracy Scott</contributor>
   <contributor role="author" last-active="1.2">Craig Setera</contributor>
+  <contributor role="author" last-active="2.10">Elad Shahar</contributor>
   <contributor role="author" last-active="2.10">shark0r</contributor>
   <contributor role="author" last-active="2.8">Peter Sikking</contributor>
   <contributor role="author" last-active="2.8">RyōTa SimaMoto</contributor>