Check returns more carefully and fix miscalculation for text spans
Update InterfacePtr ctor calls to UseDefaultIID() from IID_ #defs
Fix using wrong delete operator to tidy up arrays

Also make the TextIterator update work the way it was intended in layout_span_with_spacing()
Fix bug #1 TrueType Fonts are removed from InD font list by Grind

Trying to get IFontInstance::FillOutGlyphIDs() to fill out zero glyph ids even when passed an empty buffer cause it to Release the FontInstances parent IPMFont object. This evenutally causes the font to be destroyed in the InD app itself, rmoeving it from the UI font list.