#35 hxcomp searched for registry in incorrect path for Studio7.1

[netduke]

version nantcontrib-0.85-20040524

The hxcomp task throws an exception "Unable to locate
installation directory of Microsoft Help 2.0 SDK in the
registry."
This seems to happen because in HxCompTasks.cs the
get method for ProgramFileName seems to search in a
hardcoded path "Software\Microsoft\VisualStudio\7.0
\ .." for the registry key. This fails if there is an
installation of only Visual Studio 7.1 in the system.

The get method should probably search for the
installation of visual studio to get its version.