Add order into route_handlers
Make public/ files available to Dancer2::Test

Problem: I broke a lot of tests. Tomorrow I'll look into them with detail.
Call handler.file.before_render just before render
Clear splat attribute if route failed.
Remove route handlers hash.

Instead of having a hash and an array, use only the array. Rearrange
code to use the array everywhere.
spacing for readability
Use _params instead of params
reflect change
Merge branch 'fix/412'