Icons: Add module icon

.icons/module.png.license

@@ -0,0 +1,3 @@
+SPDX-License-Identifier: CC-BY-3.0
+SPDX-FileCopyrightText: lorc
+Original file from https://game-icons.net/1x1/lorc/jigsaw-piece.html

.icons/rebuild.py

@@ -11,6 +11,7 @@
 game_icons = {
         "board": ("lorc", "circuitry"),
         "app": ("delapouite", "keyboard"),
+        "module": ("lorc", "jigsaw-piece"),
         }
 
 for (outname, (author, iconname)) in game_icons.items():

README.md

@@ -25,9 +25,9 @@ Projects using RIOT OS
 
 Icons indicate that the project offers
 hardware descriptions (![oshw]),
-a RIOT board description (![board])
+a RIOT board description (![board]),
+RIOT modules (![module])
 or RIOT applications (![app]).
-<!-- Right now we have nothing on the list that is modules only, could get https://game-icons.net/1x1/lorc/jigsaw-piece.html as an icon then -->
 
 * ![board] ![app] [MiniLoon](https://www.hackster.io/386121/miniloon-60a9c9): A RIOT powered balloon with sensors to monitor it's environment and an App that can display these information.
 * ![oshw] ![board] ![app] [Marian's Business Card](https://github.com/maribu/business-card): Hardware description, board support, games and text display software for business card sized board with USB power supply.
@@ -41,3 +41,4 @@ More lists
 [oshw]: .icons/oshw.svg "PCB available as Open Hardware"
 [board]: .icons/board.png "RIOT OS board definition available"
 [app]: .icons/app.png "Application available"
+[module]: .icons/module.png "RIOT modules available"