from_fpga added to spead_meta_issue_all

cal_spead_meta_issue contains from_fpga parameter that allows
issue of calibration values as defined in config rather than reading
them from the fpga. This parameter now exposed at spead_meta_issue_all
to spead up issue of meta-data.
Merge branch 'master' of github.com:ska-sa/corr
Merge branch 'master' of https://github.com/ska-sa/corr
Must recreate spead tx when changing IP or port.
Merge branch 'master' of https://github.com/ska-sa/corr
centre_frequency, bandwidth update

centre_frequency assumed to be the centre of the (N/2)th channel
(starting from 0).
bandwidth assumed to be the total analogue bandwidth carried by
channels broadcast but may not be a contiguous band.

The problem is that the 0th channel may carry different frequency
components depending on if the whole band is being broadcast or not.
The frequency band represented by the 0th channel is thus ambiguous
and it should be discarded.
Merge branch 'master' of github.com:ska-sa/corr
Merge branch 'master' of https://github.com/ska-sa/corr
KATCP wrapper as currently running for beamformer after ATR