iPro: moved HTML property classes to a new unit.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@45809 4005530d-fff6-0310-9dd1-cebe43e6787f
iPro: Explode "with" blocks in TIpHtmlNodeSELECT.Reset and move common code to sub-function.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@45810 4005530d-fff6-0310-9dd1-cebe43e6787f
iPro: Explode "with" blocks in TIpHtmlNodeSELECT.CreateControl and move common code to sub-functions.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@45811 4005530d-fff6-0310-9dd1-cebe43e6787f
iPro: separate TIpHtmlProps to its own unit.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@45812 4005530d-fff6-0310-9dd1-cebe43e6787f