Fixed threading issue in async requests.
spead data and timestamp id removal

These are now hardcoded in gateware and not set from software.
Works with rev 361 and above.
Merge branch 'master' of github.com:ska-sa/corr
more verbose error in write_int

Error now reports which FPGA had the failure
spead send_halt() instead of end() in tx_stop()

using end() in tx_stop destroys the spead transmitter for meta data.
Transmitting more fails and requires a call to reinitialise or
config_meta_output. using send_halt instead so that transmitter still
available
cal configuration value changes

Each input now has bf_cal_default config setting
cal performance changes

When issuing meta data, calibration settings read from config, converted
to values that would be written to the fpga, then converted back. This is
quicker than reading from fpga.

bug fix: each beam now tracks its own inputs as not all inputs are connected
to each beam as was assumed previously
set_passband meta data issue

set_passband would only issue meta-data when transmission enabled.
Now emits any time called.

Removal of unused spead_config function
spead data descriptor bug fix

size and shape were switched around in call to ndarray. SPEAD receiver
could not unpack heaps
Merge branch 'master' of https://github.com/ska-sa/corr
SPEAD tidy up

beng_raw was specifying largest size possible and not actual size. Also
emitted now when passband changes.

cal data now emitted as floats rather than 32 bit integers.

int_time removed from SPEAD meta-data output.
offset by one error

output data was being labelled wrong by 1. Fixed
Merge branch 'master' of https://github.com/ska-sa/corr
Clean up some debug remnants