* Update `add_license` script
* run script
* add `remove duplicate lines script` and run it
* Revert changes `English spaces`
* strip whitespaces
* Revert `GPL` in files with `apache/mit license`
* don't append `gpl license` in files with other lic
* Don't append `gpl header` in files with other lic.
* re-ran script
* include c and cpp files too
* remove duplicate header
* rebase nit
* Alter IO queueing.
* Don't require IoMessages to be Clone
* Ancient blocks imported via IoChannel.
* Get rid of private transactions io message.
* Get rid of deadlock and fix disconnected handler.
* Revert to old disconnect condition.
* Fix tests.
* Fix deadlock.
