Fix grammar: Dices -> Dice in the Dice widget

Dice is already the correct plural form in English, dices is not standard.
Updated all user-visible occurrences in the Dice widget help text and
i18n properties file. (#dices) was left unchanged as it is internal
code, not UI text.

Fixes #1438

Signed-off-by: ElmotiemSofian <sofianelmotiem@gmail.com>

Author: SofianElmotiem

resources/library/interactivities/Dice.wgt/i18n/Messages.properties

@@ -1,4 +1,4 @@
-fr.njin.i18n.document.title = Dices
+fr.njin.i18n.document.title = Dice
 
 fr.njin.i18n.toolbar.edit = Edit
 fr.njin.i18n.toolbar.view = Display
@@ -10,5 +10,5 @@ fr.njin.i18n.parameters.label.slate.themes = slate
 fr.njin.i18n.parameters.label.pad.themes = pad
 fr.njin.i18n.parameters.label.none.themes = none
 
-fr.njin.i18n.de.parameters.label.count = Number of dices
+fr.njin.i18n.de.parameters.label.count = Number of dice
 fr.njin.i18n.de.actions.label.launch = Roll !

resources/library/interactivities/Dice.wgt/js/help-template.js

@@ -1,13 +1,13 @@
-<h3>Dices</h3>
+<h3>Dice</h3>
 <h4>For oral calculation or for various games</h4>
 
-<p>The dices interactivity allows you to display random dices faces.</p>
+<p>The dice interactivity allows you to display random dice faces.</p>
 <p>By clicking on the arrow or on "Launch" button, you have a new set of results. You can work the oral calculation with the displayed results or play to "the account is good".</p>
 <p>The calculations and reasoning can be written on the white board (outside the App).</p>
 <p>Enter the "Edit" mode to :</p>
 <ul>
 <li>choose the theme of the App : pad, slate, or none (by default : pad),</li>
-<li>determine the number of dices you want to use for your activity (1-6).</li>
+<li>determine the number of dice you want to use for your activity (1-6).</li>
 </ul>
 <p>The calculations and reasoning could be written on the page (outside the App).</p>
 <p>"Display" button comes back to the activity.</p>