Strip spaces from tenant name in collectd plugins

If the Tenant name includes spaces, the collectd plugins will pass
invalid data to Carbon, causing these errors to frequently appear
in Carbon's listener.log:

"invalid line received from client 10.1.2.3:33672, ignoring"
Merge pull request #9 from DavidWittman/collectd-sanitize-tenant-name

Strip spaces from tenant name in collectd plugins