blockchaininterfaces other than BitcoinCoreInterface don't sync imported privkeys

[chris-belcher]

Noticed this while reading their source code

To fix, something like this code..

joinmarket/joinmarket/blockchaininterface.py

Lines 867 to 876 in 8c2b6d8

	request = urllib2.Request('http://localhost:' + str(
	self.base_server.server_address[1] + 1) + self.path)
	request.get_method = lambda: 'HEAD'
	try:
	urllib2.urlopen(request)
	except urllib2.URLError:
	pass
	self.send_response(200)
	# self.send_header('Connection', 'close')
	self.end_headers()

..must be added to each of their sync_addresses() function

Also nobody noticed for the months and months that the importing privkey feature has existed.