require bundler 1.5.1
require bundler 1.5.1

to get ruby 2.1 as a platform for the gemfile
also make the gemfile stricter (and more helpful) on bundler version
mismatch (it used to not check the bundler version requirement if
the rest of the bundle checked out)

Change-Id: I1cc5122f3b2f0ea212a5cfd2259308026efb0f50
Reviewed-on: https://gerrit.instructure.com/27891
Tested-by: Jenkins <d95b56ce41a2e1ac4cecdd398defd7414407cc08@instructure.com>
Reviewed-by: Brian Palmer <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@instructure.com>
Product-Review: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>
QA-Review: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>

antoniuslin/canvas-lms,matematikk-mooc/canvas-lms,redconfetti/canvas-lms,redconfetti/canvas-lms,instructure/canvas-lms,SwinburneOnline/canvas-lms,grahamb/canvas-lms,fronteerio/canvas-lms,grahamb/canvas-lms,grahamb/canvas-lms,SwinburneOnline/canvas-lms,AndranikMarkosyan/lms,venturehive/canvas-lms,greyhwndz/canvas-lms,skmezanul/canvas-lms,wye0220/shindig-canvas,fronteerio/canvas-lms,usmschuck/canvas,gbleydon/canvas-lms,redconfetti/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,jay3126/canvas-lms,greyhwndz/canvas-lms,shidao-fm/canvas-lms,shidao-fm/canvas-lms,kyroskoh/canvas-lms,wye0220/shindig-canvas,tgroshon/canvas-lms,wrdsb/canvas-lms,sdeleon28/canvas-lms,roxolan/canvas-lms,sfu/canvas-lms,wrdsb/canvas-lms,efrj/canvas-lms,usmschuck/canvas,SwinburneOnline/canvas-lms,efrj/canvas-lms,Unow/canvas-lms,efrj/canvas-lms,sfu/canvas-lms,landonwilkins/canvas-lms,jay3126/canvas-lms,matematikk-mooc/canvas-lms,eCNAP/CANVAS,AndranikMarkosyan/lms,djbender/canvas-lms,leftplusrightllc/canvas-lms,Jyaasa/canvas-lms,gbleydon/canvas-lms,arrivu/arrivu-lms,arrivu/hoodemo,utkarshx/canvas-lms,Rvor/canvas-lms,dgynn/canvas-lms,narigone/canvas,juoni/canvas-lms,va7map/canvas-lms,Jyaasa/canvas-lms,arrivu/arrivu-lms,greyhwndz/canvas-lms,efrj/canvas-lms,fronteerio/canvas-lms,wye0220/shindig-canvas,utkarshx/canvas-lms,whalejasmine/canvas-lms,utkarshx/canvas-lms,dgynn/canvas-lms,usmschuck/canvas,roxolan/canvas-lms,eCNAP/CANVAS,va7map/canvas-lms,roxolan/canvas-lms,eCNAP/CANVAS,tgroshon/canvas-lms,antoniuslin/canvas-lms,samuels410/greatlakes-lms,shidao-fm/canvas-lms,samuels410/greatlakes-lms,grahamb/canvas-lms,skmezanul/canvas-lms,greyhwndz/canvas-lms,ShreniiNepal/shrenii_lmp,narigone/canvas,leftplusrightllc/canvas-lms,sfu/canvas-lms,jay3126/canvas-lms,snehakachroo1/LSI_replica,tgroshon/canvas-lms,HotChalk/canvas-lms,HotChalk/canvas-lms,venturehive/canvas-lms,kyroskoh/canvas-lms,arrivu/arrivu-lms,va7map/canvas-lms,dgynn/canvas-lms,whalejasmine/canvas-lms,djbender/canvas-lms,narigone/canvas,antoniuslin/canvas-lms,whalejasmine/canvas-lms,sdeleon28/canvas-lms,landonwilkins/canvas-lms,Unow/canvas-lms,wrdsb/canvas-lms,arrivu/hoodemo,roxolan/canvas-lms,juoni/canvas-lms,venturehive/canvas-lms,arrivu/hoodemo,instructure/canvas-lms,leftplusrightllc/canvas-lms,matematikk-mooc/canvas-lms,tgroshon/canvas-lms,usmschuck/canvas,Rvor/canvas-lms,samuels410/greatlakes-lms,juoni/canvas-lms,narigone/canvas,SwinburneOnline/canvas-lms,venturehive/canvas-lms,HotChalk/canvas-lms,AndranikMarkosyan/lms,instructure/canvas-lms,skmezanul/canvas-lms,fronteerio/canvas-lms,AndranikMarkosyan/lms,matematikk-mooc/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,kyroskoh/canvas-lms,instructure/canvas-lms,Unow/canvas-lms,instructure/canvas-lms,ShreniiNepal/shrenii_lmp,antoniuslin/canvas-lms,Rvor/canvas-lms,landonwilkins/canvas-lms,ShreniiNepal/shrenii_lmp,gbleydon/canvas-lms,whalejasmine/canvas-lms,snehakachroo1/LSI_replica,snehakachroo1/LSI_replica,grahamb/canvas-lms,snehakachroo1/LSI_replica,redconfetti/canvas-lms,skmezanul/canvas-lms,Jyaasa/canvas-lms,va7map/canvas-lms,djbender/canvas-lms,jay3126/canvas-lms,leftplusrightllc/canvas-lms,kyroskoh/canvas-lms,wrdsb/canvas-lms,HotChalk/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,sdeleon28/canvas-lms,utkarshx/canvas-lms,sdeleon28/canvas-lms,dgynn/canvas-lms,juoni/canvas-lms,instructure/canvas-lms,ShreniiNepal/shrenii_lmp,shidao-fm/canvas-lms,Jyaasa/canvas-lms,landonwilkins/canvas-lms,Rvor/canvas-lms,samuels410/greatlakes-lms,eCNAP/CANVAS