Use doc.getitemvalue("fldName") instead doc.fldName

I think many developers for receiving value from field usually wrote next code:
...
dim n as integer
n = doc.fldName(0)
...

but they have to know that this code has some weak sides:
- it slowly then doc.GetItemValue("fldName")(0) near 15-20%;
- if in new version of Lotus Notes will appear new method with name "fldName" the application will work wrong