0.09:
  - load the authors of ticket histories
  - fix assert_login for login pages without a search form.

0.08:
  - load ticket author as an Net::Redmine::User object

0.07:
  - Crawl 'date' of ticket histories.
  - improve the way handling login
  - let the 0th history entries means the "creation of this ticket"
  - ticket creation time is now loaded

0.06:
  - Improve search function.

0.05:
  - Implement ticket identity mapping in Ticket class now.
  - Loading the same ticket id multiple times with the same connection object should return identical objects.
  - fix memory leaking of ticket objects.

0.04:
  - Implement ticket deletion
  - Implement ticket refresh method
  - Implement ticket search
  - The ticket class methods are changed and it is incompatible with previous versions.

0.03:
  - Implement ticket status changes
  - Implement ticket history

0.02:
  - Implement a top-level Net::Redmine API
  - Implement ticket identity mapping using Net::Redmine APIs

0.01:
  _ Implement Ticket creating and loading.
