proposal framework for api nodes documentation

i am working on a draft to add to the wiki as i think we have no document to cover specifically the api node configuration:

https://github.com/oxarbitrage/worker-proposals/blob/master/bitshares_api_node.md

it is just a draft at the moment.

This will include https://github.com/bitshares/bitshares-core/issues/624 and https://github.com/bitshares/bitshares-core/issues/550

I will go ahead and get the commands for everything in there if you give me the ok to continue with it. Need help with securing the connection part as i never made it myself!