Client should default to true for ssl verification

[cpenner461]

We are currently defaulting verify=False when creating the StackdIO client. We should default that to True, and then if the user sets that to False, print a warning message, then suppress additional warnings that are coming from urllib3 (otherwise they are constantly spewed out).

[clarkperkins]

@cpenner461 @WLPhoenix So interesting caveat to this, when you're using a stackdio server with http and NOT https, defaulting verify to true crashes the CLI, saying that the "certificate verify failed". I have to set verify to false to get plain http working.

[clarkperkins]

Actually, turns out I must have changed my CLI to point to stackd.corp and not realized it. Now that I have it back on my own stackdio instance it works fine.

[WLPhoenix]

Should be fixed w/ #14