change asdf:run-shell-command to uiop:run-program
fix SHELLY_HOME for cygwin
fix to use directory to get absolute path

on SBCL in Windows, from was redundant. (ex. "foo/bar/baz/./" )
directory function fix this. (ex. "foo/bar/baz")
fix SHELLY_LISP_BINARY for Cygwin

*current-lisp-path* return path divided by "\" on Windows.
but Cygwin require divided by "/".