Fix increment coalescing integration tests for HBase 0.98
Fix increment coalescing integration tests for HBase 0.98

HBase 0.98 no longer creates a KV when we increment by zero,
so just work around that in our test.

This fixes #78.

OpenTSDB/asynchbase,pythian/asynchbase,Connexity/asynchbase,manolama/asynchbase,Connexity/asynchbase,manolama/asyncbigtable,hhshuai/asynchbase,manolama/asynchbase,OpenTSDB/asynchbase,OpenTSDB/asyncbigtable,SteamShon/asynchbase,nvoron23/asynchbase,tempbottle/asynchbase,yuzhu712/asynchbase,yuzhu712/asynchbase,tsuna/asynchbase,angushe/asynchbase,tsuna/asynchbase,SteamShon/asynchbase,nvoron23/asynchbase,angushe/asynchbase,hhshuai/asynchbase,tempbottle/asynchbase