Add the license block and BaseConnection
Add the license block and BaseConnection

pika/pika,fkarb/pika-python3,benjamin9999/pika,Zephor5/pika,reddec/pika,jstnlef/pika,Tarsbot/pika,vrtsystems/pika,renshawbay/pika-python3,hugoxia/pika,zixiliuyue/pika,knowsis/pika,skftn/pika,shinji-s/pika,vitaly-krugl/pika