Updated instructions to force bundler to 1.3.5 [1/1]

Updated the instructions for setting up an Ubuntu build VM to force
bundler to 1.3.5 since the prior instructions would install 1.5.1, which
does not work.


 doc/devguide/development/dev-vm-Ubuntu.md |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Crowbar-Pull-ID: 0e652a210a25077c00ed62602483118b18c0040d

Crowbar-Release: development