When using Russian Rubles, display the full currency symbol rather than just '.'

Fixes #2737
Remove backend+frontend from .travis.yml, add promo

That's what I get for blindly copying it over from the master branch
Backend shouldn't exist in 1-3-stable
Rescue from DestroyWithOrdersError only if it's defined

Fixes #2877
[cmd] Ensure there is a linebreak before gem lines inserted before installer

Fixes #2798
Allow the description to go straight to the page raw.

Fixes #2874
Make OrderPopulator error messages translatable

Fixes #2845
[sample] Remove duplicate master variants for ror_baseball_jersey and spree_baseball_jersey products

Fixes #2783
Don't show coupon code field if there are no promos with coupon codes

Fixes #2835