Moved all SWE and SWE-GLib related files under swe-glib/

!!!WARNING!!!   The build system is not updated to reflect this! The
!!!WARNING!!!   whole point is to subtree the swe-glib/ directory,
!!!WARNING!!!   making SWE-Glib a separate project as it intended to be.
Changed source to build with external SWE-GLib
Removed SWE-GLib from the source tree after making it a separate project
Updated README.md to reflect recent changes