Bug 851060 - Move util files into the util/ folder. r=cpeterson

--HG--
rename : mobile/android/base/ActivityResultHandler.java => mobile/android/base/util/ActivityResultHandler.java
rename : mobile/android/base/ActivityResultHandlerMap.java => mobile/android/base/util/ActivityResultHandlerMap.java
rename : mobile/android/base/GeckoBackgroundThread.java => mobile/android/base/util/GeckoBackgroundThread.java
rename : mobile/android/base/GeckoEventListener.java => mobile/android/base/util/GeckoEventListener.java
rename : mobile/android/base/GeckoEventResponder.java => mobile/android/base/util/GeckoEventResponder.java
rename : mobile/android/base/GeckoJarReader.java => mobile/android/base/util/GeckoJarReader.java
rename : mobile/android/base/INIParser.java => mobile/android/base/util/INIParser.java
rename : mobile/android/base/INISection.java => mobile/android/base/util/INISection.java
rename : mobile/android/base/UiAsyncTask.java => mobile/android/base/util/UiAsyncTask.java
Bug 802130 - Move assertOnThread functions to a new ThreadUtils class. r=mfinkle
Bug 802130 - Move mMainHandler into ThreadUtils. r=mfinkle
Bug 802130 - Move GeckoAppShell.getHandler() to ThreadUtils.getBackgroundHandler(). r=mfinkle
Bug 802130 - Add a ThreadUtils.isOnUiThread helper function. r=mfinkle