Move parts from FileIO to GeoLib/IO and BaseLib/IO.

Also remove unused includes.

The std::string has a build-in capability of boost::optional.

Using PointVec::getItemNameByID instead of TemplateVec::getNameOfElementByID.

http://www.viva64.com/en/d/0216/print/

http://www.viva64.com/en/d/0212/print/

gml-reader will now abort when name-tag is empty; removed superfluous warnings in qt-reader (already covered by validator)

changed the gml-standard to require z-coordinates for points, changed qt-gml-interface to avoid problems based on PR comments to boost

This should fix some issues when hashfiles contain newline characters.

- Also the xml file is read only once
- XMLQtInterface is now responsible for reading and validating the file
  (see XMLQtInterface::readFile())
- Added QByteArray XMLQtInterface::_fileData for caching the file

These references are now hardcoded in the class constructors of the
XML-IO classes. Also the definition of the two search paths in
BaseLib::FileFinder from the main window are now moved into the
constructor of FileFinder.

XML schema files are first searched (for validation) by their path
and then by the reference in the XML file itself.

Xsd are searched for on the opengeosys.org website. This fixes the
60 seconds xml reader timeout bug.

The two tests are combined because there execution order is important
which is not guaranteed in gtest.