[CMake] set CMAKE_INSTALL_PREFIX in CMakeLists

[tomasoni at sbc.su.se]

Dear Cmake users,

1) I am trying to set CMAKE_INSTALL_PREFIX in the CMakeLists file with
SET(CMAKE_INSTALL_PREFIX, "my/path")
but the variable remain unset; everything works fine if the variable is
set on the command line when invoking cmake
(-DCMAKE_INSTALL_PREFIX=my/path).

2) I am also looking for a way to avoid having to invoke cmake -G"Eclipse
CDT4 - Unix Makefiles" option. Can I set it in the CMakeLists?

Trying to avoid my users some typing...

Thank you as usual,
Mattia