Changed is_init_packet_sent to is_powercycle_on
Made data queued until radio is on, and then sent
Made queued data sent after radio is on 2 times
Made tone-sending breakpoint in send_packet()
Made tone sent at the tone-sending breakpoint
Completed single-hop single-packet one-time SCP-MAC
Made single-hop single-packet(?) one-time SCP-MAC(more stable)
Made S/R nodes synchronized even after data transmission
Added README
Cleared unnecessary codes
Updated README
Merge pull request #1 from leehankyeol/develop

Single-hop, single-packet, and lazy-ass-bastard SCP-MAC