doc: mention ServeFile change in go1.6.html
doc: mention ServeFile change in go1.6.html

Also fix a few bad links.

Change-Id: If04cdd312db24a827a3c958a9974c50ab148656c
Reviewed-on: https://go-review.googlesource.com/18979
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/go,sndnvaps/go,derekmarcotte/go,codestation/go,ImJasonH/go,Endika/go,akutz/go,sndnvaps/go,4ad/go,ganboing/go-esx,nawawi/go,theif519/go,josharian/go,vsekhar/elastic-go,CAFxX/go,goodlang/good,Samurais/go,goodlang/good,sndnvaps/go,nawawi/go,vanloswang/go,Cofyc/go,miolini/go,linux-on-ibm-z/go,akutz/go,polyverse-security/go,ganboing/go-esx,vsekhar/elastic-go,mwhudson/go,derekmarcotte/go,binarycrusader/go,akutz/go,nawawi/go,derekmarcotte/go,nawawi/go,Cofyc/go,CAFxX/go,mwhudson/go,cloudflare/go,polyverse-security/go,codestation/go,sndnvaps/go,cloudflare/go,sndnvaps/go,4ad/go,polyverse-security/go,mwhudson/go,akutz/go,polyverse-security/go,ImJasonH/go,codestation/go,cloudflare/go,Endika/go,sndnvaps/go,akutz/go,polyverse-security/go,theif519/go,ImJasonH/go,miolini/go,josharian/go,CAFxX/go,mwhudson/go,josharian/go,suncycheng/go,vsekhar/elastic-go,golang/go,CAFxX/go,Cofyc/go,cloudflare/go,CAFxX/go,binarycrusader/go,Samurais/go,goodlang/good,Cofyc/go,Endika/go,josharian/go,ImJasonH/go,golang/go,ImJasonH/go,vanloswang/go,CAFxX/go,theif519/go,derekmarcotte/go,momchil-velikov/go,theif519/go,ImJasonH/go,Samurais/go,theif519/go,vanloswang/go,suncycheng/go,ganboing/go-esx,theif519/go,suncycheng/go,4ad/go,Endika/go,nawawi/go,Endika/go,linux-on-ibm-z/go,golang/go,ganboing/go-esx,Endika/go,linux-on-ibm-z/go,binarycrusader/go,mwhudson/go,golang/go,binarycrusader/go,Samurais/go,miolini/go,codestation/go,josharian/go,momchil-velikov/go,polyverse-security/go,cloudflare/go,vsekhar/elastic-go,akutz/go,Cofyc/go,4ad/go,vanloswang/go,Endika/go,miolini/go,momchil-velikov/go,Cofyc/go,akutz/go,binarycrusader/go,ImJasonH/go,4ad/go,polyverse-security/go,theif519/go,suncycheng/go,Cofyc/go,nawawi/go,vanloswang/go,goodlang/good,linux-on-ibm-z/go,momchil-velikov/go,akutz/go,suncycheng/go,Samurais/go,josharian/go,miolini/go,suncycheng/go,codestation/go,goodlang/good,ImJasonH/go,codestation/go,miolini/go,Endika/go,suncycheng/go,linux-on-ibm-z/go,4ad/go,vanloswang/go,ganboing/go-esx,linux-on-ibm-z/go,ganboing/go-esx,4ad/go,vanloswang/go,cloudflare/go,momchil-velikov/go,mwhudson/go,CAFxX/go,vanloswang/go,goodlang/good,goodlang/good,derekmarcotte/go,josharian/go,vsekhar/elastic-go,4ad/go,derekmarcotte/go,miolini/go,Samurais/go,derekmarcotte/go,linux-on-ibm-z/go,goodlang/good,theif519/go,vsekhar/elastic-go,binarycrusader/go,golang/go,Cofyc/go,ganboing/go-esx,CAFxX/go,golang/go,sndnvaps/go,sndnvaps/go,cloudflare/go,binarycrusader/go,polyverse-security/go,mwhudson/go,momchil-velikov/go,momchil-velikov/go,nawawi/go,josharian/go,codestation/go,derekmarcotte/go,suncycheng/go,mwhudson/go,binarycrusader/go,vsekhar/elastic-go,miolini/go,Samurais/go,codestation/go,vsekhar/elastic-go,momchil-velikov/go,christopher-henderson/Go,cloudflare/go,Samurais/go,ganboing/go-esx,golang/go,linux-on-ibm-z/go,nawawi/go