[enh] Add changelog for 1.6.8. Fix doc for node v12

doc/changelog/changelog_v1.6.8.md

+# Version v1.6.8
+
+## All platforms
+
+- [enh] Build: upgrade to cordova@10.0.0, and node.js v12. Refactor Cordova hook to use main gulpfile.js
+- [fix] Map: optimize loading time (remove the search layer)
+
+## Web extension
+
+- [enh] Handle G1 link, like 'web+june://' - See [this post](https://forum.duniter.org/t/g1link-syntax-review-choisissons-la-syntaxe-g1lien/7522)
+
+## Android
+
+- [enh] Handle G1 link, like 'june://' - See [this post](https://forum.duniter.org/t/g1link-syntax-review-choisissons-la-syntaxe-g1lien/7522)
+ 
+## Desktop
+
+- [fix] Fix startup error on Ubuntu 20+ - [#921](https://git.duniter.org/clients/cesium-grp/cesium/-/issues/921)
\ No newline at end of file

doc/development_guide.md

@@ -3,7 +3,7 @@
 ## In a post-it
 
 ```bash
-nvm use 10
+nvm use 12
 git clone git@git.duniter.org:clients/cesium-grp/cesium.git
 cd cesium
 yarn
@@ -22,7 +22,7 @@ To build Cesium, you will have to:
       sudo apt-get install git wget curl unzip build-essential software-properties-common ruby ruby-dev ruby-ffi gcc make
    ```
 
-2. Installing node.js v10 :
+2. Installing node.js v12 :
 
   * First, install [nvm](https://github.com/nvm-sh/nvm) (Node Version Manager) :    
     ```bash
@@ -35,7 +35,7 @@ To build Cesium, you will have to:
 
   * Configure nvm to use the expected version: (**WARNING**: upper version will NOT work !) 
     ```bash
-       nvm install 10
+       nvm install 12
     ```
       
 3. Installing node build tools, as global dependencies:
@@ -65,9 +65,9 @@ To build Cesium, you will have to:
 
    This should create new directories `platforms/android` and `platforms/ios`.
 
-   > As a reminder: check that your command line is configured correctly:
+   > As a reminder: check that your command line is well configured:
    > - You must place yourself in the directory of the application: `cd cesium`
-   > - and working with NodeJs **v10**: `nvm use 10` (please check using the command `node --version`)
+   > - and working with NodeJs **v12**: `nvm use 12` (please check using the command `node --version`)
     
 
 ### Prepare configuration file

doc/fr/development_tutorial-03-android.md

@@ -119,7 +119,7 @@ node --version
 Si vous n'êtes pas sur une v6, utilisez la commande 
 
 ```
-nvm use 10
+nvm use 12
 ```
 
 Vous pouvez maintenant lancer l'instalaltion du projet Cesium pour Android :