[Cmake] new features

[Bill Hoffman]

I have checked in several new features to cmake:

1. .NET IDE support (Visual Studio 7)

2. you can now create semi-colon separated lists in cmake variables.
For example,

# create a variable LIBS that has a, b, c
SET(LIBS a;b;c)

# now use LIBS
LINK_LIBRARIES(${LIBS})  
# this is the same as this:
LINK_LIBRARIES(a b c)

This should allow CMakeLists.txt files to provide single points where
libraries are listed. 


3. Internal path clean up.   All the generators now
use cmSystemTools::ConvertToOutputPath to create output paths, and
all paths are stored as unix paths internally.   


I expect to make a new release within the next month.   Please give
the cvs version a try and let me know if there are any problems with
any of the above changes.

-Bill