Misc. typos

+ some are doxy others are just comment code.  
+ some minor whitespace and grammatical tweaks. 
+ app/SCL/* typos have also been submitted upstream (https://github.com/stepcode/stepcode/pull/366). So it's ok to merge them in to master.

src/Mod/Material/materials-editor.ui

@@ -227,7 +227,7 @@
             <string>Source</string>
            </property>
            <property name="toolTip">
-            <string>An optional description of where the informations included in this card come from</string>
+            <string>An optional description of where the information included in this card comes from</string>
            </property>
            <property name="flags">
             <set>ItemIsSelectable|ItemIsEditable|ItemIsDragEnabled|ItemIsUserCheckable|ItemIsEnabled</set>