v3.4.0

[notgull]

• Add the ability to identify whether socket connection has failed. (feat : add the ability to identify if tcp connection has failed #185)
• On BSD, add the ability to wait on a process by its PID. Previously, it was
  only possible to wait on a process by a Child object. (Add a way to wait on process by PID #180)
• On ESP-IDF, annotate eventfd initialization failures with a message
  indicating the source of those failures. (Annotate ESP-IDF EPERM error with eventfd info #186)