mergeSeries() needs runtime normalizing

[Dieterbe]

feeding some fake data into MT and changing its resolution, then querying it, triggers this:

metrictank_1    | [Macaron] PANIC: runtime error: index out of range [10798] with length 90
metrictank_1    | /usr/lib/go/src/runtime/panic.go:75 (0x42dae2)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/api/dataprocessor.go:661 (0xbc7fae)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/api/graphite.go:782 (0xbcfd9c)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/api/graphite.go:251 (0xbca50b)
metrictank_1    | /usr/lib/go/src/reflect/value.go:460 (0x4b1925)
metrictank_1    | /usr/lib/go/src/reflect/value.go:321 (0x4b10e3)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:177 (0xa926f9)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:137 (0xa920a9)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:121 (0xaadde8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:112 (0xb14855)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/api/middleware/logger.go:43 (0xb1483e)
metrictank_1    | /usr/lib/go/src/reflect/value.go:460 (0x4b1925)
metrictank_1    | /usr/lib/go/src/reflect/value.go:321 (0x4b10e3)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:177 (0xa926f9)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:137 (0xa920a9)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:121 (0xaadde8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:112 (0xb15ecd)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/api/middleware/tracer.go:67 (0xb15eb8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:79 (0xaadc90)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:157 (0xa92409)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:135 (0xa92198)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:121 (0xaadde8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:112 (0xb155ed)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/api/middleware/stats.go:76 (0xb155d8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:79 (0xaadc90)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:157 (0xa92409)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:135 (0xa92198)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:121 (0xaadde8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:112 (0xbb8c0d)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/raintank/gziper/gzip.go:100 (0xbb8c00)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:79 (0xaadc90)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:157 (0xa92409)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:135 (0xa92198)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:121 (0xaadde8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:112 (0xabeab9)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/recovery.go:161 (0xabeaa7)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/logger.go:40 (0xab1963)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:157 (0xa92409)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/github.com/go-macaron/inject/inject.go:135 (0xa92198)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/context.go:121 (0xaadde8)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/router.go:187 (0xabfcd6)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/router.go:294 (0xaba10d)
metrictank_1    | /home/dieter/go/src/github.com/grafana/metrictank/vendor/gopkg.in/macaron.v1/macaron.go:220 (0xab2cda)
metrictank_1    | /usr/lib/go/src/net/http/server.go:2802 (0x743883)
metrictank_1    | /usr/lib/go/src/net/http/server.go:1890 (0x73f224)
metrictank_1    | /usr/lib/go/src/runtime/asm_amd64.s:1357 (0x45f3b0)

this is on v0.13.1-298-g8ebb187d

looks like in #951 we forgot to add runtime normalization to mergeSeries()