Fix various typos [skip ci]

Fixed via 
```
codespell -q 3 -L aci,ake,aline,alle,alledges,alocation,als,ang,anid,ba,beginn,behaviour,bloaded,byteorder,calculater,cancelled,cancelling,cas,cascade,centimetre,childs,colour,colours,commen,currenty,dof,doubleclick,dum,eiter,elemente,feld,freez,hist,iff,indicies,initialisation,initialise,initialised,initialises,initialisiert,ist,kilometre,lod,mantatory,methode,metres,millimetre,modell,nd,noe,normale,normaly,nto,numer,oder,orgin,orginx,orginy,ot,pard,pres,programm,que,recurrance,rougly,seperator,serie,sinc,strack,substraction,te,thist,thru,tread,uint,unter,vertexes,wallthickness,whitespaces -S ./.git,*.po,*.ts,./ChangeLog.txt,./src/3rdParty,./src/Mod/Assembly/App/opendcm,./src/CXX,./src/zipios++,./src/Base/swig*,./src/Mod/Robot/App/kdl_cp,./src/Mod/Import/App/SCL,./src/WindowsInstaller,./src/Doc/FreeCAD.uml
```

src/Mod/AddonManager/Resources/icons/Manipulator_workbench_icon.svg

@@ -380,7 +380,7 @@
             <rdf:li>cross</rdf:li>
           </rdf:Bag>
         </dc:subject>
-        <dc:description>Four equally sized arrow heads at 90° to eachother, all joined at the tail</dc:description>
+        <dc:description>Four equally sized arrow heads at 90° to each other, all joined at the tail</dc:description>
       </cc:Work>
     </rdf:RDF>
   </metadata>