Added an "m=metric{tagk1=tagv1,...}" style query parameter to the /api/uid/tsmeta endpoint. Allows for retrieving the TSMeta of a time series without knowing the TSUID, only be specifying the timeseries using the metric and tags.
Removed obsolete FIXME and added a (currently not working) test.
Fixed and added tests for new TSMeta query type:
- checks whether metadata is correctly retrieved via metric name + tag
- checks that correct tsuid is generated with multiple tags
- checks that BadRequest Exception is thrown when timeseries does not exist.
Added tests for invalid syntax in query, catching IllegalArgumentException from Tags.parseWithMetric and turning it into a BadRequest.
Merge branch 'opentsdb-next' into next

Pulling fixes to treesync.
A first draft of POST HTTP API call that generates a TSMeta object for a timeseries that does not yet exist, i.e., where no datapoint was saved so far. Metric and tag UIDs have to exist though.
On inserting the first datapoint, we now check whether there already exists a TSMeta and only create a new one if that's not the case. Passing newly created TSMeta objects via /api/uid/tsmeta now also through tree processing.
revert accidental reformatting
more finals, throwing BadRequest Exception when metric string can not be parsed
made preallocation of ByteBuffer more robust, respecting the configured UID width
merged post TSMeta by metric and tags code
Merge branch 'next_lastdp' of https://github.com/OpenTSDB/opentsdb into next
Get TSMeta by query now uses the new TSUIDQuery class. Can potentially return multiple TSMetas.
POST by metric and tags. Needs to be enabled explicitly by create=true flag in the URL. If specified creates both a TSMeta object and initializes the counter.
check that TSMeta really exists before returning it.
before accepting a TSMeta POST/PUT via m-query, check whether TSMeta exists (not the counter), since a counter might exist without a TSMeta. We need to know whether the TSMeta exists however.
Integrated comments from https://github.com/OpenTSDB/opentsdb/pull/230.

Major changes:
* No redundant lookup of TSMeta. Changed the scanner to return the correct column.
* UniqueIdRpc now returns a List of TsMetas.
Added an "m=metric{tagk1=tagv1,...}" style query parameter to the
/api/uid/tsmeta endpoint. Allows for retrieving the TSMeta of a time series
without knowing the TSUID, only be specifying the timeseries using the
metric and tags.
Enabled creation of TSMeta objects via POST by metric and tags. Needs to be
enabled explicitly by create=true flag in the URL. If specified creates
both a TSMeta object and initializes the counter.
Formatting fixes