Bug 1012981 - Generate unique password and show it to the user

Replaces the static password to more secure unique, generated password and shows it to the user:
* when creates the application from the web ui
* when creates the app with `rhc app create --from-app [...]`
* when creates the cartridges and pushes the quickstart via git

Also add instructions in case of web ui timeout

[Bug 1012981](https://bugzilla.redhat.com/show_bug.cgi?id=1012981) (and also [related](https://bugzilla.redhat.com/show_bug.cgi?id=1013684))
Basically we need the stored password for one reason: the user should be able to see the generated password later (online ui timeout, just forgot to note).

I managed to send result back from the deploy script which we execute only when the user has no configured site. Currently, we use the password there to create an admin account. I can move the password generate and client_result to the deploy script as well if we don't care the use-case above.