Fix where the documentation says "photos", but the example shows "posts" or "comments" by switching both to simply "posts"

Add further documentation + examples for the get, post, put and delete methods in ActionDispatch::Routing::Mapper::HttpHelpers

Raise ArgumentError instead of normalizing controller name when there is a leading slash [#5651 state:resolved]

Ported missing functionality from Rails 2.3.x, raise error on wrong regexps in :constraints in routes

mounted_helpers are a bit similar to url_helpers. They're automatically
included in controllers for Rails.application and each of mounted
Engines. Mounted helper allows to call url_for and named helpers for
given application.

Given Blog::Engine mounted as blog_engine, there are 2 helpers defined:
app and blog_engine. You can call routes for app and engine using those
helpers:

app.root_url
app.url_for(:controller => "foo")
blog_engine.posts_path
blog_engine.url_for(@post)

* added more tests for prefix generation
* fixed bug with generating host for both prefix and url
* refactored url_for method
* organized tests for prefix generation

This requires knowledge about original SCRIPT_NAME and
the parent router. It should be pass through the env
as ORIGIAL_SCRIPT_NAME and action_dispatch.parent_routes

This technique is here to allow using routes from Engine in Application
and vice versa. When using Engine routes inside Application it should
generate prefix based on mount point. When using Engine routes inside
Engine it should use env['SCRIPT_NAME']. In any other case it should
generate prefix as env should not be even available.

Move implicit nested call before options handling so that nested constraints work [#5513 state:resolved]
Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

If you were using symbols before for methods like match/get/post/put/delete, it is likely that this commit will break your routes.
Everything should behave the same if you are using strings, if not, please open up a ticket.