Found reason for progressBar not displaying.
The progressBar is hidden away after going through the "Fragment Activity Cycle" once.
Changed implementation to use Java List instead of Java Array.
Merge branch 'composer'

Conflicts:
	app/src/main/java/com/pianoshelf/joey/pianoshelf/Main.java
hotfix for sheetmusic url
Merge branch 'composer'
Implemented a generic JSON Adapter
Changed class to abstract and hotfix for getItemId
Utilize JSONAdapter to simplify ComposerAdapter
list type for sheet music querying.
Basic skeleton code finished.
Needs UI suger-coating.
added spinning progressbar to composerView
Merge branch 'sheetListView'