Add cross browser shims file
Add cross browser shims file

This file currently includes a helper for normalising inline-block
across browsers. It takes an optional min-height argument.

alphagov/govuk_frontend_toolkit,alphagov/govuk_frontend_toolkit,quis/govuk_frontend_toolkit,quis/govuk_frontend_toolkit,alphagov/govuk_frontend_toolkit,alphagov/govuk_frontend_toolkit,quis/govuk_frontend_toolkit,TFOH/govuk_frontend_toolkit,TFOH/govuk_frontend_toolkit,ministryofjustice/govuk_frontend_toolkit,quis/govuk_frontend_toolkit,TFOH/govuk_frontend_toolkit,ministryofjustice/govuk_frontend_toolkit,TFOH/govuk_frontend_toolkit