Update RSpec to 2.99.0
Use rspec-its to suppress deprecation warning

```
Use of rspec-core's `its` method is deprecated. Use the rspec-its gem instead.
```
Replace deprecated methods

* `be_true` -> `be_truthy`
* `be_false` -> `be_falsey`
Add option to specify example group in automatically

```
rspec-rails 3 will no longer automatically infer an example group's spec type
from the file location. You can explicitly opt-in to this feature using this
snippet:

RSpec.configure do |config|
  config.infer_spec_type_from_file_location!
end

If you wish to manually label spec types via metadata you can safely ignore
this warning and continue upgrading to RSpec 3 without addressing it.
```
Upgrade RSpec to 3.0
Replace RSpec syntax `should` -> `expect`
Suppress deprecation warning

```
Requiring `rspec/autorun` when running RSpec via the `rspec` command is deprecated.
```
Merge pull request #36 from tricknotes/update-rspec

Update RSpec to 3.0