Updated readme with ergo node requirements #61
Description
Although this might seem obvious to everyone who was involved in the development of chaincash that an ergo node has to be running locally for the server to operate, this is not very obvious to a newer set of eyes. The readme needs to be updated to state the software that needs to be running. Also, the chaincash server should explicitly state the versions of ergo node it supports. I tried running it with verison 6.0.0 of ergo node only to waste two days trying to figure out errors. Tried it with ergo node version 5.0.24 and everything worked. Specifically , the ergoTree data structure was giving issues when chaincash server tried to parse it values from the node in version 6.0.0