Reload/check for new comments on post every X seconds

[code-with-sam]

User may be commenting via alternative interface, we can check if there are new comments and append any that are new.

from : https://steemit.com/finallycomments/@sambillingham/finally-comments-is-now-on-steemprojects-com#@dailypro/re-sambillingham-finally-comments-is-now-on-steemprojects-com-20180509t151423631z