Update bundled gems

I ran `bundle update`. I think/hope this'll make it easier to upgrade to
Rails 4.
Specify Ruby 2.0.0

I've additionally specified 2.0.0-p247 (which is the version on
Heroku[1]) in .ruby-version even though that's not in the repo.

All the tests pass on my laptop so I'm hoping they'll pass on Travis and
that it'll all just work once deployed to Heroku.

[1] https://devcenter.heroku.com/articles/ruby-support#ruby-versions
Fix asset precompilation

Running `rake assets:precompile` failed on Heroku (and locally) with the
following error: "'fontawesome.less' wasn't found". This change (as per
the README[1]) fixes the problem in development and will hopefully do
the same on Heroku.

[1] https://github.com/seyhunak/twitter-bootstrap-rails/#icons
Remove use of attr_protected

This is no longer required as I'm using strong parameters. Removing this
now should make the upgrade to Rails 4 go a little smoother.
Upgrade to Rails 4.0.1

I ran `rails new money-tracker` from this app's parent directory and
then went through each of the changed files and manually merged their
contents where applicable.

I've had to disable turbolinks (it was added to application.js by
default) to avoid the 'Editing multiple transactions with javascript'
test from failing. Everything appeared to work OK in development even
with turbolinks enabled.
Avoid deprecation warning with default scope

The warning was:

DEPRECATION WARNING: Calling #default_scope without a block is
deprecated. For example instead of `default_scope where(color: 'red')`,
please use `default_scope { where(color: 'red') }`.
Fix broken exception notifier config

Prior to this, I was seeing the following error in the Heroku logs:

    undefined method `new' for ExceptionNotifier:Module (NoMethodError)

The info on upgrading is in the Exception Notifier README[1].

[1] https://github.com/smartinez87/exception_notification#upgrading-to-4x-version
Add Heroku rails_12factor gem

Apparently this is required for a Rails 4 app to serve assets in
production[1].

[1] http://stackoverflow.com/questions/15354539/heroku-does-not-compile-files-under-assets-piplines-in-rails-4
Merge branch 'upgrade-to-rails-4'

All the tests pass and I've tested that it correctly deploys to Heroku.
Update README

Update the instructions to download/import a database dump from ./tmp
rather than the app directory.

Add a newline to the end of the file.
Add autocomplete to the Location field

This is similar to the commits that added autocomplete to the
descriptions[1] and categories[2]. The difference here is that the set
of location options are dependent on the description field, in order to
limit the set of possibilities.

I wasn't able to use the simple format of `autocomplete` in
application.js, as I need to get hold of the description at the time I
make the request to get the set of autocomplete suggestions. Setting the
`source` option to a string doesn't allow me to do this.

I've added an additional 'transaction' class to the form element in the
edit template, so that I can target the transaction container given the
location field.

[1] d94e1bd7add127f773e6dd1c5c0972d34e6625f6
[2] c7a0ca0d14097eda9aad129a97e4e8182c32038f
Remove unnecessary #encoding comments

These are no longer necessary as utf-8 is the default encoding in Ruby
2.
Remove .gitkeep files

Rails now uses .keep files instead of .gitkeep. Running the Rails 4
setup over the top of this existing repo means that I've now got the
.keep files.

I renamed a couple of the '.gitkeep' files to '.keep', where the
equivalent .keep file didn't exist.

I found the '.gitkeep' files with: `find . -name ".gitkeep" | grep -v
".bundle"`.
Remove vendor/plugins

This is no longer supported by Rails so I'm removing it.
Add rubocop to the development group

I've used this in the past to check my code against the Ruby Style
Guide[1]. I figure that it won't do any harm to keep it in the
development group of the repo.

[1] https://github.com/bbatsov/ruby-style-guide
Add newlines to the end of each file

As is good practice generally, and recommended in the Ruby Style Guide.
Display account name against transaction on edit pages.
Add simple script to export transactions as CSV

I can imagine that I might build this into the app at some point, but
this'll do for now.