Fix typos and whitespace

Found via `codespell -q 3 -L aci,ake,aline,alle,alledges,alocation,als,ang,anid,anormal,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,itsel,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,ro,rougly,seperator,serie,sinc,siz,strack,substraction,te,technic,thist,thru,tread,uint,unter,uptodate,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/Base/StackWalker.cpp,./build/doc/SourceDocu`

src/Mod/TechDraw/Gui/DlgPrefsTechDrawAnnotationImp.cpp

@@ -48,7 +48,7 @@ DlgPrefsTechDrawAnnotationImp::DlgPrefsTechDrawAnnotationImp( QWidget* parent )
     ui->setupUi(this);
     ui->pdsbBalloonKink->setUnit(Base::Unit::Length);
     ui->pdsbBalloonKink->setMinimum(0);
-    
+
     // connect the LineGroup the update the tooltip if index changed
     connect(ui->pcbLineGroup, SIGNAL(currentIndexChanged(int)),
         this, SLOT(onLineGroupChanged(int)));
@@ -98,7 +98,7 @@ void DlgPrefsTechDrawAnnotationImp::loadSettings()
     for (auto it = lgNames.begin(); it < lgNames.end(); ++it) {
         ui->pcbLineGroup->addItem(tr((*it).c_str()));
     }
- 
+
     ui->cbAutoHoriz->onRestore();
     ui->cbPrintCenterMarks->onRestore();
     ui->cbPyramidOrtho->onRestore();
@@ -147,7 +147,7 @@ void DlgPrefsTechDrawAnnotationImp::onLineGroupChanged(int index)
         ui->pcbLineGroup->setToolTip(QObject::tr("Please select a Line Group"));
         return;
     }
-    // get the definition the the selected LineGroup (includes the name)
+    // get the definition of the selected LineGroup (includes the name)
     std::string lgRecord = LineGroup::getRecordFromFile(Preferences::lineGroupFile(), index);
     std::stringstream ss(lgRecord);
     std::vector<std::string> lgNames;