[ci skip] Add a Delayed Job project link.
[ci skip] Add a Delayed Job project link.

Delayed Job is mentioned multiple times in the document, but it is not linked from anywhere.
rafaelfranca/omg-rails,Stellenticket/rails,schuetzm/rails,BlakeWilliams/rails,kmcphillips/rails,arunagw/rails,yahonda/rails,Edouard-chin/rails,MSP-Greg/rails,MSP-Greg/rails,Envek/rails,kddeisz/rails,mechanicles/rails,palkan/rails,joonyou/rails,lcreid/rails,jeremy/rails,prathamesh-sonpatki/rails,georgeclaghorn/rails,bogdanvlviv/rails,flanger001/rails,shioyama/rails,tjschuck/rails,Envek/rails,palkan/rails,tjschuck/rails,BlakeWilliams/rails,eileencodes/rails,flanger001/rails,EmmaB/rails-1,lcreid/rails,prathamesh-sonpatki/rails,yalab/rails,BlakeWilliams/rails,betesh/rails,joonyou/rails,utilum/rails,palkan/rails,arunagw/rails,Edouard-chin/rails,Edouard-chin/rails,notapatch/rails,bogdanvlviv/rails,bogdanvlviv/rails,eileencodes/rails,fabianoleittes/rails,jeremy/rails,jeremy/rails,Stellenticket/rails,yalab/rails,Envek/rails,shioyama/rails,tgxworld/rails,schuetzm/rails,kmcphillips/rails,yhirano55/rails,tgxworld/rails,vipulnsward/rails,palkan/rails,tjschuck/rails,repinel/rails,joonyou/rails,Erol/rails,gauravtiwari/rails,yalab/rails,starknx/rails,betesh/rails,yhirano55/rails,starknx/rails,utilum/rails,yhirano55/rails,iainbeeston/rails,rails/rails,Stellenticket/rails,EmmaB/rails-1,fabianoleittes/rails,notapatch/rails,fabianoleittes/rails,betesh/rails,yhirano55/rails,prathamesh-sonpatki/rails,kmcphillips/rails,yawboakye/rails,Vasfed/rails,shioyama/rails,notapatch/rails,flanger001/rails,utilum/rails,rails/rails,esparta/rails,betesh/rails,jeremy/rails,tgxworld/rails,fabianoleittes/rails,shioyama/rails,georgeclaghorn/rails,repinel/rails,tgxworld/rails,arunagw/rails,vipulnsward/rails,rafaelfranca/omg-rails,kddeisz/rails,gauravtiwari/rails,bogdanvlviv/rails,Vasfed/rails,tjschuck/rails,BlakeWilliams/rails,starknx/rails,esparta/rails,esparta/rails,repinel/rails,yawboakye/rails,Envek/rails,lcreid/rails,joonyou/rails,schuetzm/rails,Erol/rails,rafaelfranca/omg-rails,yahonda/rails,kddeisz/rails,yawboakye/rails,schuetzm/rails,notapatch/rails,vipulnsward/rails,esparta/rails,vipulnsward/rails,arunagw/rails,Stellenticket/rails,kddeisz/rails,Erol/rails,kmcphillips/rails,rails/rails,iainbeeston/rails,georgeclaghorn/rails,yahonda/rails,lcreid/rails,iainbeeston/rails,rails/rails,gauravtiwari/rails,Vasfed/rails,Vasfed/rails,yawboakye/rails,mechanicles/rails,yalab/rails,flanger001/rails,mechanicles/rails,MSP-Greg/rails,Edouard-chin/rails,iainbeeston/rails,EmmaB/rails-1,eileencodes/rails,yahonda/rails,eileencodes/rails,georgeclaghorn/rails,MSP-Greg/rails,Erol/rails,mechanicles/rails,repinel/rails,prathamesh-sonpatki/rails,utilum/rails