Fix email validation error I18n symbol lookup

And include %{value} for interpolation in validation messages.

The current code hardcodes the I18n key and improperly assigns the error
which leads to several problems:
* You cannot override the translation message for models/attributes
* You cannot pass your own I18n key as a symbol (eg. :invalid_email)
* You cannot use symbol interpolation

This fixes the above problems and is the proper solution for issue #2346.

This fix also applies to 1-2-stable and 1-3-stable.
For a fix against 1-1-stable see PR #2729.

Fixes #2730
nested_taxons_path will now take a Taxon object and generate a proper URL
Fixes orders#show title for i18n cases

Fixes #2784
When a calculator is using a preference of type :text, a textarea is shown. The calculator.js should disable/enable this textarea the same as the input from a preference of any other type.

Fixes #2782
Correct content length check in base_helper_spec test for meta_data_tags
Switch the mailers to be invoked using ids, not model objects. This makes it easier to support asynchronous mail jobs, as only simple ids need to be persisted.

Fixes #2806
Revert premature merging of #2806

Revert "Switch the mailers to be invoked using ids, not model objects. This makes it easier to support asynchronous mail jobs, as only simple ids need to be persisted."

This reverts commit a3f1d3bbaf841a735a8697133ed12870bb446148.
Use separate databases depending on the value of ENV['TC_AGENT_NUMBER']
Remove invalid duplicate line-items id in shared/_order_details.html.erb

This has now been moved to the <table> tag which contains both these elements.

Fixes #2836
Allow sample to generate its own testing app
Switch the mailers to be invoked using ids, not model objects. This makes it easier to support asynchronous mail jobs, as only simple ids need to be persisted.

Fixes #2806
Fix tax calculator with non-VAT taxes.

This is an issue with Spree line items and tax rate calulators.

The method used to subtract tax from a VAT did not play nicely
with non value added taxes.

Fixes #2870
Bump to selenium-webdriver 2.32.0

Conflicts:
	common_spree_dependencies.rb
Recalculate product count_on_hand when ANY of its variants are saved

Fixes #2799

Conflicts:
	core/app/models/spree/variant.rb
only show eligible adjustments on the backend
Return html_safe strings from variant_price_diff

Fixes #2737
[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
Correct documentation for title helper

Fixes #2878
Only set ActiveMerchant::Billing::Base if gateway_options[:server] is available