Include my_key prompt message

[n1ur0]

Small addition to prompt a message so user can write its API Key name and use it when starting its node.

[ladopixel]

Hi n1ur0,

It seems to me a very good idea, although now your code is not quite correct. We also need to check if ergo.conf exists to get out of the loop. As it is now, it asks for the name every time the node is started, even if ergo.conf is already created.
To know if the ergo.conf file exists we must know if it was created in the default directory or in one chosen by the user.