2.1

Changes:

• Fix for missing client certificates (#43)
• Keepalive enabled for all the TCP connections
• Introduction of root_ca flag
• Server clients flag is now optional, by default any client can connect
• Client insecure_skip_verify flag removed, the behavior is automatically on when root_ca is empty
• Removal of log-to flag, everything is logged to stderr
• Panics replaced by errors in the library
• Release builds do not contain debug symbols

Thanks you @goriccardo for your contributions!