Fix decodeTags to decode tags correctly from encodeTags
Fix decodeTags to decode tags correctly from encodeTags

encodeTags would encode the tags by outputting every key followed by
every value in alphabetical order. decodeTags would try to read this in
an old format that printed tags in key/value order.

This fix matches decodeTags to match the same format encodeTags outputs.

archsaber/influxdb,vladlopes/influxdb,li-ang/influxdb,vladlopes/influxdb,jgeiger/influxdb,influxdata/influxdb,archsaber/influxdb,jipperinbham/influxdb,mnuessler/influxdb,otoolep/influxdb,pkittenis/influxdb,runner-mei/influxdb,otoolep/influxdb,daachi/influxdb,influxdb/influxdb,joaopedrotaveira/influxdb,mark-rushakoff/influxdb,otoolep/influxdb,pkittenis/influxdb,jgeiger/influxdb,nooproblem/influxdb,arussellsaw/influxdb,joaopedrotaveira/influxdb,influxdb/influxdb,mark-rushakoff/influxdb,runner-mei/influxdb,linearb/influxdb,mnuessler/influxdb,apigee/influxdb,pkittenis/influxdb,mark-rushakoff/influxdb,influxdb/influxdb,influxdb/influxdb,jgeiger/influxdb,apigee/influxdb,otoolep/influxdb,daachi/influxdb,jipperinbham/influxdb,daachi/influxdb,mnuessler/influxdb,archsaber/influxdb,vladlopes/influxdb,benbjohnson/influxdb,influxdb/influxdb,daachi/influxdb,pkittenis/influxdb,apigee/influxdb,otoolep/influxdb,pkittenis/influxdb,mnuessler/influxdb,benbjohnson/influxdb,linearb/influxdb,jipperinbham/influxdb,mark-rushakoff/influxdb,benbjohnson/influxdb,archsaber/influxdb,nooproblem/influxdb,joaopedrotaveira/influxdb,apigee/influxdb,otoolep/influxdb,mark-rushakoff/influxdb,joaopedrotaveira/influxdb,chenziliang/influxdb,arussellsaw/influxdb,mnuessler/influxdb,mnuessler/influxdb,jipperinbham/influxdb,jipperinbham/influxdb,arussellsaw/influxdb,linearb/influxdb,mark-rushakoff/influxdb,daachi/influxdb,arussellsaw/influxdb,benbjohnson/influxdb,jgeiger/influxdb,li-ang/influxdb,influxdata/influxdb,nooproblem/influxdb,jgeiger/influxdb,pkittenis/influxdb,apigee/influxdb,jipperinbham/influxdb,chenziliang/influxdb,arussellsaw/influxdb,jgeiger/influxdb,vladlopes/influxdb,runner-mei/influxdb,chenziliang/influxdb,arussellsaw/influxdb,daachi/influxdb,linearb/influxdb,nooproblem/influxdb,influxdb/influxdb,chenziliang/influxdb,runner-mei/influxdb,apigee/influxdb,linearb/influxdb,nooproblem/influxdb,joaopedrotaveira/influxdb