quick fix for #614 (no webview on old devices)

 * fixes #614 by invoking the browser intent on old devices again
 * also the alert dialog warning will be shown
 * new option to disable this dialog
fixes Brick looking different on some devices

fixes #295 by lifting the 9.png left-bottom-border pixel up.

Devices which will be (at least) fixed are:
 * Nexus S (4.1.2)
 * Nexus 7 (4.2.2 - 2012 Edition)
Merge pull request #621 from Catrobat/issue#614

quick fix for #614 (no webview on old devices)
Merge pull request #622 from Catrobat/fixed9png

fixes Brick looking different on some devices
Merge remote-tracking branch 'catrobat/master' into issue#570
broadcast bricks