[+] cursors closes after loading [+] sync button in actionbar creates dummy data
[-] sync button doesn't create dummy data anymore [~] hasAccounts method queries over db instead of calling getAccounts method
[+] add base interface for all type of fragments [+] add contextual actionbar for category dialog
[~] create base function class for all fragments, so that all different types (like dialogs or fragments) can use same functionality
[~] changed comment