iOS: WaveFormView/WaveFormCacheManager: Fixed bug where the wave form would not be updated right after generating the peak file.

Related to issue #405.
PeakFileService: Fixed bug where the Cancelled status was always false. This did not allow proper cancel in WaveFormCacheManager.
MobileNavigationManager: Now reusing a single instance of IPlayerView.

Related to issue #405 and issue #409.
Merge branch 'master' of https://github.com/ycastonguay/MPfm