Merge pull request #991 from vuntz/no-slash-in-secure-pw

Do not accept / in secure passwords
Merge pull request #988 from vuntz/better-proposal-name

Better proposal name
Change how we deal with multi-proposals barclamps in list of barclamps

Until now, when a multi-proposal barclamp had no proposal, we were just
displaying a Create button that created a proposal named "default". And
then, later on, we were allowing the creation of new proposals with
different names.

Since "default" is not a great name and people will likely want to
change this, we now directly allow creating proposals with any name.