French translation (#48)

* Create strings.xml

* Create array.xml

Author: Poussinou

app/src/main/res/values-fr/array.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+
+    <string-array name="fontSizeTitles">
+        <item>Très petit</item>
+        <item>Petit</item>
+        <item>Normal</item>
+        <item>Grand</item>
+        <item>Très grand</item>
+    </string-array>
+
+</resources>

app/src/main/res/values-fr/strings.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">ArchWiki Viewer</string>
+    <string name="menu_settings">Paramètres</string>
+    <string name="share">Partager le lien</string>
+    <string name="search">Chercher</string>
+    <string name="exit">Quitter</string>
+    <string name="text_size_preference">Taille du texte</string>
+    <string name="refresh">Rafraîchir</string>
+</resources>