Link to API docs in Routing guide [ci-skip]
Link to API docs in Routing guide [ci-skip]

This links the first mention of each method to its API documentation,
similar to a Wikipedia article.  Some subsequent mentions are also
linked, when it suits the surrounding text.

This also modifies the text in a few places to ensure that methods are
explicitly mentioned (and linked) before they appear in code examples.

joonyou/rails,lcreid/rails,yawboakye/rails,rails/rails,Edouard-chin/rails,Erol/rails,kmcphillips/rails,betesh/rails,yawboakye/rails,Envek/rails,yahonda/rails,rails/rails,Envek/rails,Erol/rails,bogdanvlviv/rails,MSP-Greg/rails,BlakeWilliams/rails,EmmaB/rails-1,joonyou/rails,rails/rails,kmcphillips/rails,georgeclaghorn/rails,tjschuck/rails,Vasfed/rails,Vasfed/rails,lcreid/rails,Vasfed/rails,bogdanvlviv/rails,EmmaB/rails-1,esparta/rails,yawboakye/rails,Edouard-chin/rails,yawboakye/rails,Envek/rails,BlakeWilliams/rails,eileencodes/rails,EmmaB/rails-1,Stellenticket/rails,BlakeWilliams/rails,georgeclaghorn/rails,kddeisz/rails,yahonda/rails,kddeisz/rails,yahonda/rails,MSP-Greg/rails,joonyou/rails,tgxworld/rails,esparta/rails,georgeclaghorn/rails,tgxworld/rails,rails/rails,Vasfed/rails,bogdanvlviv/rails,lcreid/rails,Stellenticket/rails,MSP-Greg/rails,bogdanvlviv/rails,kmcphillips/rails,Envek/rails,eileencodes/rails,eileencodes/rails,tgxworld/rails,betesh/rails,Erol/rails,Edouard-chin/rails,lcreid/rails,esparta/rails,esparta/rails,tjschuck/rails,kddeisz/rails,tgxworld/rails,georgeclaghorn/rails,BlakeWilliams/rails,MSP-Greg/rails,tjschuck/rails,Edouard-chin/rails,betesh/rails,kddeisz/rails,kmcphillips/rails,joonyou/rails,eileencodes/rails,tjschuck/rails,yahonda/rails,betesh/rails,Stellenticket/rails,Stellenticket/rails,Erol/rails