Remove dojo specific code

[jscott1989]

• Design needs to be made generic
• Logo should be configurable
• Event Titles should be generic or customisable
• EventSolution should be moved into its own module
• Membership options should be moved into configuration
• Payment details passed to Stripe should be configurable
• Notification URLS should be configurable
• Mail from address should be configurable
• Social links should be configurable
• Allow configuration of the word "event"/"dojo"/etc.
• Index page should be customisable like other pages
• Membership text should be configurable
• Default email templates should be configurable

[jscott1989]

Sponsorship has been pulled out into a plugin and the plugin architecture has been created.

The next step for this is to pull out Event Solutions, Comments, Membership options, payment, and social links.

[jscott1989]

Made event titles customisable

[jscott1989]

Comments have been pulled out into a plugin

[jscott1989]

Event Solutions (Groups) have been pulled out into a plugin. The "github_url" still needs to be turned into a configuration variable though.

[jscott1989]

Mail from address should be configurable and Allow configuration of the word "event"/"dojo"/etc.

complete.

[jscott1989]

Payment settings are now configurable

[jscott1989]

Membership is now a separate module and dojo-specific things are gone.

However it still only supports dojo-style 1-year pay-what-you-want membership. This will be changed as part of #58

[jscott1989]

All dojo specific code has now been removed except for the social links and emails. For emails see #5 and for social links see #60