made EntryLogs and Summary tabbed fragments that MainActivity uses.
included the sign out functionality in MainActivity
added the created files to the pull request
added an additional comment in EntryLogsTab
merged with master
deleted EntryLogsActivty and SummaryActivity
fixed LogoActivity lauching into a fragment
RegisterActivity should go to MainActivity, not EntryLogsTab
added author in SummaryTab
Merge pull request #115 from coldstar96/tabbed-app

Tabbed app