Removing non existent items from params to avoid bug when clicking on remove multiple times or when clicking on multiple remove buttons

Skipping filter if there is only one line item being updated

Fixing order controller spec

Dealing with case when line items attributes is nil

Fixes #5318
Fix item_adjustment_spec.rb

Test after tax_adjustments callback instead of after promo_adjustments, which was testing a few lines earlier
Fixes #5320
Only cancel cancellable shipments.

Fixes #5321
Fixes #5299
Update Ruby hash syntax to 1.9

Create Spree::Core::ControllerHelpers::StrongParameters test
Fixes #5322
Allow partial emails when searching for orders
Fixes #5314