first draft of the calendar view and timeline
FileBrowser: Setting tabs to unclosable
TogglePane: parent component for ui switching
MetadataBrowser: toggle between search and nav

However, the search field is not functional for now.
MetadataBrowser: stubs for button actions
MetadataBrowser: import cleanup
ProjectListDialog: swap first and second line in list item
TwoLineListCell: hopefully nicer style
MetadataBrowser: use two line list cells
StatementTableItem: fix value display for non string types
Merge pull request #66 from stoewer/gndata-editor-56-metabrowse

Further improved metadata bowser
FileBrowser: Refactoring LocalFile methods
FileBrowser: Setting tabs to unclosable
FileBrowser: Refactoring LocalFile methods
Merge branch 'filebrowser' of github.com:mpsonntag/gndata-editor into filebrowser
refactored query pane with new table item
Merge branch 'dev' of github.com:asobolev/gndata-editor into dev
moved table test to the util package
simple clenup in Calendar view
FileBrowser: Adding toggle pane, search field to navigation bar