readme: emphasize issue tracker is for bugs/proposals
readme: emphasize issue tracker is for bugs/proposals

Removed direct link to issue tracker in the README - it makes it too
easy to use it for a question - and it's abused multiple times a day
for questions. It's easy enough to find it if there's a real issue
to report.

Added sentence to point people at golang-nuts and the new forum.

Change-Id: If75bab888cda064aceeefc49ef672fbb964f8f54
Reviewed-on: https://go-review.googlesource.com/15284
Reviewed-by: Jason Buberel <8b0dded81f03028981dc6a6c3a92c3428b82e077@google.com>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/go,josharian/go,Cofyc/go,vanloswang/go,rachtsingh/gogojuice,codestation/go,CAFxX/go,binarycrusader/go,momchil-velikov/go,gdey/go,binarycrusader/go,theif519/go,golang/go,deft-code/go,polyverse-security/go,goodlang/good,dterei/go,dterei/go,dterei/go,deft-code/go,ImJasonH/go,malvira/go,akutz/go,fjballest/golang,linux-on-ibm-z/go,4ad/go,mwhudson/go,fjballest/golang,rachtsingh/gogojuice,mwhudson/go,vanloswang/go,codestation/go,mwhudson/go,gdey/go,cloudflare/go,suncycheng/go,Endika/go,miolini/go,Endika/go,gdey/go,gdey/go,4ad/go,jacobsa/go,polyverse-security/go,Cofyc/go,gdey/go,ganboing/go-esx,gdey/go,dterei/go,Cofyc/go,miolini/go,ImJasonH/go,deft-code/go,kim-racktop/go,derekmarcotte/go,vanloswang/go,Endika/go,binarycrusader/go,nawawi/go,jacobsa/go,goodlang/good,golang/go,malvira/go,sndnvaps/go,miolini/go,rachtsingh/gogojuice,suncycheng/go,cloudflare/go,polyverse-security/go,linux-on-ibm-z/go,linux-on-ibm-z/go,odeke-em/go,vanloswang/go,codestation/go,rachtsingh/gogojuice,malvira/go,derekmarcotte/go,vsekhar/elastic-go,Jordanzuo/go,linux-on-ibm-z/go,nawawi/go,roth1002/go,vsekhar/elastic-go,cloudflare/go,dterei/go,odeke-em/go,suncycheng/go,codestation/go,goodlang/good,fjballest/golang,miolini/go,josharian/go,golang/go,cyberroadie/go,goodlang/good,nawawi/go,goodlang/good,rachtsingh/gogojuice,Jordanzuo/go,theif519/go,deft-code/go,Samurais/go,fjballest/golang,deft-code/go,Cofyc/go,vanloswang/go,sndnvaps/go,josharian/go,ganboing/go-esx,Jordanzuo/go,rachtsingh/gogojuice,Endika/go,Jordanzuo/go,derekmarcotte/go,fjballest/golang,roth1002/go,vsekhar/elastic-go,jacobsa/go,linux-on-ibm-z/go,golang/go,vanloswang/go,codestation/go,Endika/go,ganboing/go-esx,Samurais/go,ganboing/go-esx,polyverse-security/go,vsekhar/elastic-go,sndnvaps/go,mwhudson/go,polyverse-security/go,Samurais/go,Samurais/go,nawawi/go,christopher-henderson/Go,binarycrusader/go,theif519/go,derekmarcotte/go,josharian/go,momchil-velikov/go,roth1002/go,4ad/go,gdey/go,binarycrusader/go,derekmarcotte/go,roth1002/go,CAFxX/go,roth1002/go,goodlang/good,suncycheng/go,4ad/go,momchil-velikov/go,josharian/go,cyberroadie/go,odeke-em/go,malvira/go,ImJasonH/go,polyverse-security/go,Endika/go,ImJasonH/go,cloudflare/go,binarycrusader/go,odeke-em/go,odeke-em/go,ganboing/go-esx,4ad/go,roth1002/go,jacobsa/go,akutz/go,dterei/go,kim-racktop/go,momchil-velikov/go,ganboing/go-esx,akutz/go,nawawi/go,momchil-velikov/go,vsekhar/elastic-go,ImJasonH/go,kim-racktop/go,miolini/go,4ad/go,jacobsa/go,mwhudson/go,roth1002/go,malvira/go,nawawi/go,akutz/go,golang/go,kim-racktop/go,nawawi/go,CAFxX/go,mwhudson/go,goodlang/good,Cofyc/go,fjballest/golang,cyberroadie/go,rachtsingh/gogojuice,goodlang/good,golang/go,vanloswang/go,ganboing/go-esx,mwhudson/go,Cofyc/go,malvira/go,cyberroadie/go,theif519/go,cyberroadie/go,akutz/go,jacobsa/go,miolini/go,linux-on-ibm-z/go,codestation/go,rachtsingh/gogojuice,malvira/go,CAFxX/go,cyberroadie/go,cyberroadie/go,mwhudson/go,sndnvaps/go,ganboing/go-esx,Jordanzuo/go,vsekhar/elastic-go,vsekhar/elastic-go,theif519/go,derekmarcotte/go,josharian/go,vsekhar/elastic-go,CAFxX/go,odeke-em/go,odeke-em/go,CAFxX/go,kim-racktop/go,fjballest/golang,momchil-velikov/go,golang/go,akutz/go,cyberroadie/go,nawawi/go,derekmarcotte/go,josharian/go,Cofyc/go,Endika/go,codestation/go,Jordanzuo/go,Cofyc/go,gdey/go,cloudflare/go,jacobsa/go,4ad/go,derekmarcotte/go,vanloswang/go,theif519/go,momchil-velikov/go,Endika/go,cloudflare/go,ImJasonH/go,4ad/go,sndnvaps/go,linux-on-ibm-z/go,deft-code/go,Samurais/go,suncycheng/go,josharian/go,Samurais/go,kim-racktop/go,deft-code/go,linux-on-ibm-z/go,polyverse-security/go,dterei/go,ImJasonH/go,polyverse-security/go,kim-racktop/go,momchil-velikov/go,theif519/go,sndnvaps/go,cloudflare/go,jacobsa/go,odeke-em/go,miolini/go,miolini/go,suncycheng/go,CAFxX/go,codestation/go,suncycheng/go,binarycrusader/go,Jordanzuo/go,fjballest/golang,theif519/go,CAFxX/go,binarycrusader/go,Jordanzuo/go,akutz/go,sndnvaps/go,dterei/go,deft-code/go,malvira/go,kim-racktop/go,suncycheng/go,Samurais/go,Samurais/go,cloudflare/go,ImJasonH/go,roth1002/go,akutz/go,sndnvaps/go