gitignore cleanup

* ignore typical backup files created by common editors
* move general ignore rules like "*.o" or "depend.mk" to top level gitignore
* ignore executables and test directories in target dir gitignore
  as these are local and there's no general catch-all pattern for them

server/test/.gitignore

@@ -0,0 +1,7 @@
+bin/
+Documentation/
+etc/
+lib/
+log/
+modules/
+mysql/