Install 'better_errors' gem
bundle update (with some cleanup)
Add 'binding_of_caller' gem (for 'better_errors')
Format and simplify
Whitespace, alignment
Comment out redundant `accepts_nested_attributes`
Simplify use of optional locals in views
Remove obsolete parameter
Use `object`/`collection`, not `model`/`models`

Use `object` and `collection` instead of inappropriately used `model` and `models`, respectively.

`model` should be used instead of the strange `klass` to store a model (which is a class).
Use `model` instead of `klass`
More intelligent 'new' links for memberships
Format, correct
Experiment with main menu template
Add url methods in ControllerAware module
Start formatting localisation files
Associate TicketBook with Membership

Basic changes to associate TicketBook with Membership instead of MembershipType, and to nest TicketBooksController under MembershipsController.