Fix various typos

Found via `codespell -q 3 -L aci,ake,aline,alle,alledges,alocation,als,ang,anid,apoints,ba,beginn,behaviour,bloaded,bottome,byteorder,calculater,cancelled,cancelling,cas,cascade,centimetre,childrens,childs,colour,colours,commen,connexion,currenty,dof,doubleclick,dum,eiter,elemente,ende,feld,finde,findf,freez,hist,iff,indicies,initialisation,initialise,initialised,initialises,initialisiert,inout,ist,kilometre,lod,mantatory,methode,metres,millimetre,modell,nd,noe,normale,normaly,nto,numer,oce,oder,ontop,orgin,orginx,orginy,ot,pard,parm,parms,pres,programm,que,rady,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,./build/doc/SourceDocu`

src/Mod/PartDesign/App/FeatureHelix.cpp

@@ -253,7 +253,7 @@ App::DocumentObjectExecReturn* Helix::execute(void)
             mkPS.SetTransitionMode(BRepBuilderAPI_Transformed);
 
             //mkPS.SetMode(true);  //This is for frenet
-            mkPS.SetMode(TopoDS::Wire(auxpath), true);  // this is for auxilliary
+            mkPS.SetMode(TopoDS::Wire(auxpath), true);  // this is for auxiliary
 
             for (TopoDS_Wire& wire : wires) {
                 wire.Move(invObjLoc);