Radio "scan" mode

[jhansche]

Adds the ability to "Scan" radio frequencies. Virtually every car radio has this feature, so it's a feature that is sorely missing from this Radio app.

• Some of the Radio code has been cleaned up: whitespace trimmed, //TODO Auto-generated comments removed, empty Dialog click listeners removed, imports organized, etc...
• Some strings have been "translated" in the en-rUS locale, to make them more US-friendly (i.e., "Fine" -> "Tune"; "Step" -> "Seek"). These changes were done here instead of in the default values/strings.xml file, just in case that's a terminology that people outside the US are more familiar with. In USA, "Tune" and "Seek" are more familiar.

Then the Scan mode updates:

1. Long-press on the "Seek" button enters the "Scan" mode.
2. Adds a "Scan Delay" preference to configure how long to wait on each frequency before skipping to the next.

The feature is especially useful when traveling outside of your "home" area, where you aren't familiar with radio stations -- but you don't want to use the "Auto" search function, as that would wipe out all of your saved stations.

Instead, entering a scan mode simply steps to each tunable frequency, pausing between each station. If you hear a station that you'd like to stop on, you can cancel the scan mode by pressing the "Seek" button again, or by pressing the forward/backward arrow buttons.

This closes jhansche/packages_apps_bonovoapps#2

[DwaineGarden]

I can't wait to test this one out!...

[jhansche]

@DwaineGarden if you want to test it out before it's merged, you can find the APK at https://github.com/jhansche/packages_apps_bonovoapps/releases/tag/radio-160724

That includes both this and #31 (ignore the fact that the tag references the wrong commit - that was a mistake, meant to reference the radio-scan branch. The APK is the correct binary, just forgot to update the tag's starting branch)

I was using Google Drive during my testing: upload to Drive, go out to the car, wait for the 3G dongle to connect, open Drive, download the APK. It'll prompt if you want to "install the update to the system app." After it installs, the new APK will be active. Just be aware that after a restart, it will likely no longer persist (because the version codes are not kept up to date in the apps, so the system doesn't know that the downloaded version is newer than the system version).

Might be worth versioning at least the bonovo apps (and ideally, everything should be properly versioned anyway). Doing that, we should even be able to create Play Store listings for those apps, and allow OTA updates via the Play Store. That's assuming that the signing key we use here is considered "release", which it may not be. Play Store will not allow a debug or testing key to be used to publish to the play store.

[DwaineGarden]

James, you going to pull this in?