A pricing plan selection step for users with a recognized partner has
been added to the beginning of the onboarding tour. Once visited, users
have the option of purchasing the pricing plan associated with their
partner or proceeding as a paid or free tier user.
Resolves storj-private#118
Resolves storj-private#126
Change-Id: I3b423194d96deaf87cf9807a766bf4d04fbcf86d
