putting the example queries and the tutorial into one "Help" tab
Merge remote-tracking branch 'korpling/annis/develop' into develop
fixed #184 (It should always be possible to un-select a selected corpus)
fixed #191 (Double clicking on history entry throws exception)
proportions
explicitly set help tab not closeable
rearrange buttons (still ugly...)
Merged 'develop'.
icon for query builder button and some re-arranging
make the "Query Builder" button functioning
add "export" to more actions
auto-exchange options on tab change
use a tab sheet instead of an accordion
move export options to the main tab
re-enabled export
Merged 'develop'.
Merged 'develop'.

Conflicts:
	annis-gui/src/main/java/annis/gui/ExportPanel.java
better icon for query builder
query builder now has more text in order to allow easier discovery of functions by the user
use ANNIS icon for "About ANNIS" and improve the "corpus reload" icon