doc/go1.7.html: the 1.6.3 release supports Sierra
doc/go1.7.html: the 1.6.3 release supports Sierra

Updates #16354
Updates #16272

Change-Id: I73e8df40621a0a17a1990f3b10ea996f4fa738aa
Reviewed-on: https://go-review.googlesource.com/25014
Run-TryBot: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

linux-on-ibm-z/go,vsekhar/elastic-go,nawawi/go,derekmarcotte/go,polyverse-security/go,Cofyc/go,suncycheng/go,4ad/go,momchil-velikov/go,derekmarcotte/go,linux-on-ibm-z/go,4ad/go,goodlang/good,codestation/go,suncycheng/go,polyverse-security/go,Cofyc/go,josharian/go,nawawi/go,akutz/go,suncycheng/go,josharian/go,ImJasonH/go,derekmarcotte/go,CAFxX/go,momchil-velikov/go,golang/go,momchil-velikov/go,josharian/go,CAFxX/go,momchil-velikov/go,linux-on-ibm-z/go,momchil-velikov/go,codestation/go,vsekhar/elastic-go,polyverse-security/go,golang/go,momchil-velikov/go,ImJasonH/go,vsekhar/elastic-go,cloudflare/go,derekmarcotte/go,josharian/go,goodlang/good,derekmarcotte/go,akutz/go,goodlang/good,ImJasonH/go,CAFxX/go,CAFxX/go,josharian/go,derekmarcotte/go,nawawi/go,4ad/go,ImJasonH/go,goodlang/good,Cofyc/go,josharian/go,derekmarcotte/go,Cofyc/go,CAFxX/go,CAFxX/go,cloudflare/go,linux-on-ibm-z/go,josharian/go,vsekhar/elastic-go,akutz/go,goodlang/good,linux-on-ibm-z/go,polyverse-security/go,nawawi/go,cloudflare/go,goodlang/good,vsekhar/elastic-go,cloudflare/go,akutz/go,codestation/go,golang/go,golang/go,ImJasonH/go,golang/go,4ad/go,suncycheng/go,nawawi/go,suncycheng/go,codestation/go,cloudflare/go,polyverse-security/go,josharian/go,golang/go,christopher-henderson/Go,Cofyc/go,goodlang/good,CAFxX/go,polyverse-security/go,CAFxX/go,suncycheng/go,nawawi/go,akutz/go,codestation/go,polyverse-security/go,4ad/go,cloudflare/go,ImJasonH/go,codestation/go,linux-on-ibm-z/go,ImJasonH/go,akutz/go,cloudflare/go,golang/go,nawawi/go,suncycheng/go,Cofyc/go,vsekhar/elastic-go,derekmarcotte/go,ImJasonH/go,codestation/go,4ad/go,linux-on-ibm-z/go,linux-on-ibm-z/go,codestation/go,4ad/go,Cofyc/go,vsekhar/elastic-go,vsekhar/elastic-go,akutz/go,polyverse-security/go,4ad/go,suncycheng/go,nawawi/go,akutz/go,goodlang/good,momchil-velikov/go,momchil-velikov/go,Cofyc/go,golang/go,cloudflare/go