User-defined properties should be empty by default to prevent linker
failures.
* builds/windows/vc2010/freetype.user.props,
builds/windows/vc2010/freetype.vcxproj:
s/OptionsDirectory/UserOptionDirectory/.
Comment out all user options.
This simplifies custom build configurations, especially for
automated build environments.
* builds/windows/vc2010/freetype.user.props: New configuration file.
* builds/windows/vc2010/freetype.vcxproj: Include
`freetype.user.props' and use its data fields.
* builds/windows/vc2010/index.html: Updated.