Add unified GC paper

Author: jacob-hughes

softdev.bib

@@ -3314,3 +3314,12 @@ @misc{stroustrup97c++
   month=Jun,
   publisher={Addison-Wesley}
 }
+
+@inproceedings{bacon04unified,
+  title={A unified theory of garbage collection},
+  author={Bacon, David F and Cheng, Perry and Rajan, VT},
+  booktitle="OOPSLA",
+  pages={50--68},
+  month=Oct,
+  year={2004}
+}