InstallRequiredSystemLibraries does not install any dlls when
used with VS 6 dashboards. Modify the ValidateBuild script to
expect only 1 file when building with VS 6.
Using "-DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>" does not work when
<INSTALL_DIR> evaluates to a long enough string. However, using
"-DCMAKE_INSTALL_PREFIX:PATH=<INSTALL_DIR>" does work, even with
the longer strings. So: make sure to include the ":PATH" when using
this construct with ExternalProject calls so that they may install
to the proper location on VS 6 builds. All existing calls that match
"CMAKE_INSTALL_PREFIX.*INSTALL_DIR" include the ":PATH" after this
commit.
By the way: https://twitter.com/DLRdave/status/134339505397309440
537020f958