Fix #292 (Appium client shows older capabilities values)

Before merging, please could you check over these changes and ensure that everything required is sent correctly.

Both send:
* `appium-version`: `1.0`
* `platformName`: `self.model.android.platformVersion` or `iOS`
* `platformVersion`: `self.model.android.platformVersionNumber` or `self.model.iOS.platformVersion`
* `deviceName`: `self.model.android.deviceName` or `self.model.iOS.deviceName`
* `app`: `self.model.android.appPath` or `self.model.iOS.appPath`

In addition, Android sends:
* `appPackage`: `self.model.android.package`
* `appActivity`: `self.model.android.activity`

Also, I removed some imports on the Java file that didn't seem to be used. Please could you double check that this still looks ok (I don't have any Java complier installed)?