std: Clean up some annotations in thread::local
std: Clean up some annotations in thread::local

Don't need so much manual #[doc(hidden)] and #[unstable] as much of it is
inherited!

rohitjoshi/rust,jashank/rust,zubron/rust,jashank/rust,krzysz00/rust,zubron/rust,sae-bom/rust,seanrivera/rust,pshc/rust,seanrivera/rust,robertg/rust,reem/rust,ejjeong/rust,KokaKiwi/rust,jashank/rust,aidancully/rust,mdinger/rust,l0kod/rust,dwillmer/rust,andars/rust,jashank/rust,vhbit/rust,mihneadb/rust,dwillmer/rust,kwantam/rust,andars/rust,nwin/rust,GBGamer/rust,nwin/rust,graydon/rust,mihneadb/rust,pshc/rust,aidancully/rust,pelmers/rust,pshc/rust,zachwick/rust,zubron/rust,pelmers/rust,nwin/rust,rohitjoshi/rust,jroesch/rust,gifnksm/rust,reem/rust,cllns/rust,victorvde/rust,KokaKiwi/rust,sae-bom/rust,krzysz00/rust,andars/rust,jroesch/rust,zubron/rust,vhbit/rust,kwantam/rust,gifnksm/rust,cllns/rust,l0kod/rust,reem/rust,robertg/rust,zubron/rust,sae-bom/rust,aneeshusa/rust,nwin/rust,aneeshusa/rust,omasanori/rust,ejjeong/rust,victorvde/rust,krzysz00/rust,l0kod/rust,kwantam/rust,aidancully/rust,carols10cents/rust,reem/rust,pshc/rust,mvdnes/rust,KokaKiwi/rust,aepsil0n/rust,aneeshusa/rust,robertg/rust,carols10cents/rust,TheNeikos/rust,jroesch/rust,reem/rust,jashank/rust,aepsil0n/rust,andars/rust,GBGamer/rust,robertg/rust,pelmers/rust,vhbit/rust,omasanori/rust,philyoon/rust,vhbit/rust,l0kod/rust,nwin/rust,graydon/rust,l0kod/rust,dwillmer/rust,mvdnes/rust,dwillmer/rust,philyoon/rust,XMPPwocky/rust,philyoon/rust,mihneadb/rust,GBGamer/rust,zachwick/rust,nwin/rust,mihneadb/rust,mvdnes/rust,omasanori/rust,reem/rust,aepsil0n/rust,pshc/rust,andars/rust,TheNeikos/rust,graydon/rust,cllns/rust,mvdnes/rust,gifnksm/rust,aidancully/rust,seanrivera/rust,aidancully/rust,nwin/rust,ejjeong/rust,zachwick/rust,carols10cents/rust,jroesch/rust,mdinger/rust,dwillmer/rust,graydon/rust,seanrivera/rust,gifnksm/rust,l0kod/rust,krzysz00/rust,omasanori/rust,kwantam/rust,sae-bom/rust,pshc/rust,mdinger/rust,victorvde/rust,GBGamer/rust,philyoon/rust,carols10cents/rust,jroesch/rust,jroesch/rust,mvdnes/rust,XMPPwocky/rust,rohitjoshi/rust,mdinger/rust,zachwick/rust,KokaKiwi/rust,sae-bom/rust,mihneadb/rust,GBGamer/rust,andars/rust,vhbit/rust,zachwick/rust,krzysz00/rust,carols10cents/rust,aneeshusa/rust,TheNeikos/rust,philyoon/rust,ejjeong/rust,KokaKiwi/rust,mdinger/rust,zubron/rust,aidancully/rust,XMPPwocky/rust,GBGamer/rust,graydon/rust,vhbit/rust,l0kod/rust,dwillmer/rust,jroesch/rust,victorvde/rust,jroesch/rust,robertg/rust,victorvde/rust,rohitjoshi/rust,nwin/rust,aneeshusa/rust,sae-bom/rust,XMPPwocky/rust,rohitjoshi/rust,GBGamer/rust,ejjeong/rust,krzysz00/rust,vhbit/rust,pelmers/rust,ejjeong/rust,graydon/rust,XMPPwocky/rust,dwillmer/rust,GBGamer/rust,cllns/rust,zachwick/rust,dwillmer/rust,jashank/rust,jashank/rust,jashank/rust,gifnksm/rust,omasanori/rust,robertg/rust,mvdnes/rust,zubron/rust,rohitjoshi/rust,pshc/rust,mdinger/rust,philyoon/rust,cllns/rust,gifnksm/rust,TheNeikos/rust,kwantam/rust,carols10cents/rust,aepsil0n/rust,l0kod/rust,KokaKiwi/rust,pelmers/rust,seanrivera/rust,kwantam/rust,victorvde/rust,aepsil0n/rust,pshc/rust,mihneadb/rust,omasanori/rust,aepsil0n/rust,cllns/rust,TheNeikos/rust,zubron/rust,pelmers/rust,TheNeikos/rust,aneeshusa/rust,vhbit/rust,XMPPwocky/rust,seanrivera/rust