Checkpoint patch on the way to making samples/expenses bookmarkable via
activities and places. Introduces some place classes (not yet used),
but mainly reorganizes the code:

* Refactors SlidingPanel out of ExpensesShell

* Refactors a Factory class to be in charge of instantiation. More DI
/ IOC, allows use of PlaceHistoryMapper, and maybe, just maybe, we
can get GIN going.

* Refactors an app class out of the entry point, making the former
trivial.

Next steps are extracting activities out of ExpensesList and
ExpensesDetail, and making the latter work from EntityProxyIds instead
of actual proxies.

Review at http://gwt-code-reviews.appspot.com/1013801

Review by: robertvawter@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@9091 8db76d5a-ed1c-0410-87a9-c151d255dfc7
41 files changed