Re-route all traffic to alias domain name through URL rewriting

[giannifiore]

Refer to https://github.com/rebrandly/rebrandly-express/wiki/URL-rewriting-and-alias-domains

User Stories

As a Rebrandly developer,
I need the middleware to accept an alias domain name as input during its setup,
So that I can assume the alias domain name is always known at runtime

As a Rebrandly developer,
I need the middleware to re-write the incoming HTTP request following a set of rewriting rules,
So that I can make sure there is a testable module specific to URL rewriting

Acceptance Tests

Given a server running on domain acme.com
Given that acme.com was added as an alias domain in Rebrandly
Given that the alias of acme.com is xyzxyzxyz.rebrandly.cc

Given that there is no matching route for /promo
When the server running at acme.com processes https://acme.com/promo URL
Then the response is a 302 Temporary Redirect to URL https://xyzxyzxyz.rebrandly.cc/promo
When the server running at acme.com processes http://acme.com/promo URL
Then the response is a 302 Temporary Redirect to URL https://xyzxyzxyz.rebrandly.cc/promo
When the server running at acme.com processes https://acme.com/promo?super=true URL
Then the response is a 302 Temporary Redirect to URL https://xyzxyzxyz.rebrandly.cc/promo?super=true

[giannifiore]

working on it on branch url-rewriting

[giannifiore]

removed requirement of preserving "#querystring", because this value wouldn't reach server side