* fix: avoid duplicate connection
* ignore the duplicate connecting to same peer within 10 seconds
* refactor: use hashmap instead of vector for connecting history
* remove the double checking for already connected peer on connect
* add previous connecting time to the log
* fix a mistake on shrink
* move the now() into the inter loop for accurate time
* change the minimum allowed inverval time from 10s to 30s
Gary Yu
c7bb5eab27