doc: remove some TODOs from go1.8.html
doc: remove some TODOs from go1.8.html

TBR=See https://golang.org/cl/33244

Updates #17929

Change-Id: I5d92bd62b6560d245f77fa042c7e35d9eddc4994
Reviewed-on: https://go-review.googlesource.com/33683
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

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