collectd: send double correctly for gauge
collectd: send double correctly for gauge

Before the change in the metric layer, the type_value was implemented as
a union, so gauge was set as double but read as unsigned 64.

Now, it is up to the collectd to switch between the bit representations.

See scylladb/scylla#2072

Signed-off-by: Amnon Heiman <ed5fc74c4692051ad0b19749fd7cea6ec2d74b9e@scylladb.com>
Message-Id: <1487080481-29263-1-git-send-email-ed5fc74c4692051ad0b19749fd7cea6ec2d74b9e@scylladb.com>

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