cleanup: removed $Id$, which is useless now that we've migrated to git.

briefly talked about it on jabber, no one opposed to it, Jeremy explicitly
agreed.  changes are trivial themselves, so no explicit review.

src/lib/exceptions/exceptions.h

@@ -12,8 +12,6 @@
 // OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 // PERFORMANCE OF THIS SOFTWARE.
 
-// $Id$
-
 #ifndef __EXCEPTIONS_H
 #define __EXCEPTIONS_H 1