added interface ColSource
added interface ColSource

Change-Id: I995323202f42b0881c18c16cfe31a0123e3bf5f4

cambridgehackers/connectal,chenm001/connectal,chenm001/connectal,cambridgehackers/connectal,chenm001/connectal,cambridgehackers/connectal,hanw/connectal,8l/connectal,csail-csg/connectal,cambridgehackers/connectal,chenm001/connectal,hanw/connectal,chenm001/connectal,8l/connectal,csail-csg/connectal,csail-csg/connectal,hanw/connectal,8l/connectal,hanw/connectal,hanw/connectal,8l/connectal,csail-csg/connectal,cambridgehackers/connectal,8l/connectal,csail-csg/connectal