Fix typos and misc. formatting [skip ci]

Found 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/Mesh/Gui/ViewProviderTransformDemolding.cpp

@@ -200,7 +200,7 @@ void ViewProviderMeshTransformDemolding::valueChangedCallback(void)
   temp.setTransform( SbVec3f(0,0,0),    // no transformation
                      rot,               // rotation from the dragger
                      SbVec3f(1,1,1),    // no scaling
-                     SbRotation() ,     // no scaling oriantation
+                     SbRotation() ,     // no scaling orientation
                      SbVec3f(center.x,center.y,center.z)); // center of rotation
   pcTransformDrag->setMatrix( temp );
 }