auto merge of #16052 : nham/rust/fs_docs, r=brson
auto merge of #16052 : nham/rust/fs_docs, r=brson

Some of the fixes include:

 - fixing mismatch between the documentation and the function parameters. (i.e. documentation references `path` parameter, but it's actually called `from`, or vice versa)
 - A few Error sections were missing an "if" on the middle clause. For example, they used to be: "This function will return an error if [Thing], [Another Thing], or if [Yet Another Thing]." I added an "if" so it becomes "This function will return an error if [Thing], if [Another Thing], or if [Yet Another Thing]"
 - The error sections previously started off with 3 different phrases: 

     - "This function will return an error if ..."
     - "Will return an error if ..."
     - "This call will return an error if ..."

  I've standardized on the first phrase.

victorvde/rust,kimroen/rust,ebfull/rust,zaeleus/rust,cllns/rust,ruud-v-a/rust,reem/rust,nham/rust,GBGamer/rust,dinfuehr/rust,omasanori/rust,defuz/rust,nham/rust,aepsil0n/rust,pelmers/rust,GBGamer/rust,AerialX/rust,emk/rust,ejjeong/rust,mvdnes/rust,pelmers/rust,graydon/rust,pshc/rust,kwantam/rust,barosl/rust,cllns/rust,AerialX/rust-rt-minimal,carols10cents/rust,rohitjoshi/rust,aidancully/rust,vhbit/rust,andars/rust,jroesch/rust,ruud-v-a/rust,vhbit/rust,omasanori/rust,ebfull/rust,zaeleus/rust,untitaker/rust,rprichard/rust,omasanori/rust,GBGamer/rust,untitaker/rust,kwantam/rust,miniupnp/rust,bombless/rust,mdinger/rust,emk/rust,rprichard/rust,carols10cents/rust,pelmers/rust,kimroen/rust,sae-bom/rust,AerialX/rust-rt-minimal,0x73/rust,zaeleus/rust,rohitjoshi/rust,andars/rust,andars/rust,mvdnes/rust,sae-bom/rust,AerialX/rust,zachwick/rust,richo/rust,ebfull/rust,erickt/rust,quornian/rust,miniupnp/rust,emk/rust,zubron/rust,aneeshusa/rust,kimroen/rust,aneeshusa/rust,jroesch/rust,P1start/rust,KokaKiwi/rust,KokaKiwi/rust,pshc/rust,l0kod/rust,nwin/rust,cllns/rust,kimroen/rust,zubron/rust,XMPPwocky/rust,zubron/rust,barosl/rust,TheNeikos/rust,ejjeong/rust,jbclements/rust,avdi/rust,mihneadb/rust,aidancully/rust,pshc/rust,ejjeong/rust,AerialX/rust-rt-minimal,ebfull/rust,mvdnes/rust,mihneadb/rust,TheNeikos/rust,mdinger/rust,dinfuehr/rust,zachwick/rust,dwillmer/rust,mvdnes/rust,GBGamer/rust,zachwick/rust,hauleth/rust,carols10cents/rust,zubron/rust,GBGamer/rust,pshc/rust,jbclements/rust,TheNeikos/rust,aidancully/rust,rprichard/rust,barosl/rust,ejjeong/rust,P1start/rust,0x73/rust,hauleth/rust,l0kod/rust,l0kod/rust,sae-bom/rust,dwillmer/rust,mahkoh/rust,vhbit/rust,jashank/rust,andars/rust,dwillmer/rust,robertg/rust,erickt/rust,ebfull/rust,krzysz00/rust,avdi/rust,hauleth/rust,jroesch/rust,TheNeikos/rust,mihneadb/rust,reem/rust,seanrivera/rust,carols10cents/rust,reem/rust,hauleth/rust,zaeleus/rust,AerialX/rust-rt-minimal,bombless/rust,jashank/rust,l0kod/rust,dwillmer/rust,sae-bom/rust,kimroen/rust,mvdnes/rust,aneeshusa/rust,cllns/rust,rprichard/rust,jbclements/rust,rprichard/rust,seanrivera/rust,robertg/rust,hauleth/rust,TheNeikos/rust,carols10cents/rust,nwin/rust,ejjeong/rust,rohitjoshi/rust,dinfuehr/rust,KokaKiwi/rust,nham/rust,cllns/rust,ktossell/rust,zubron/rust,erickt/rust,richo/rust,philyoon/rust,KokaKiwi/rust,krzysz00/rust,cllns/rust,andars/rust,seanrivera/rust,quornian/rust,mihneadb/rust,vhbit/rust,philyoon/rust,aepsil0n/rust,ruud-v-a/rust,dwillmer/rust,0x73/rust,emk/rust,carols10cents/rust,pelmers/rust,robertg/rust,nwin/rust,jashank/rust,jbclements/rust,avdi/rust,gifnksm/rust,zubron/rust,0x73/rust,richo/rust,KokaKiwi/rust,defuz/rust,rohitjoshi/rust,GBGamer/rust,philyoon/rust,ktossell/rust,jbclements/rust,XMPPwocky/rust,krzysz00/rust,mdinger/rust,defuz/rust,untitaker/rust,defuz/rust,graydon/rust,l0kod/rust,victorvde/rust,reem/rust,richo/rust,jroesch/rust,emk/rust,krzysz00/rust,philyoon/rust,kwantam/rust,zaeleus/rust,gifnksm/rust,ktossell/rust,sae-bom/rust,defuz/rust,pelmers/rust,ruud-v-a/rust,P1start/rust,avdi/rust,dinfuehr/rust,nham/rust,victorvde/rust,seanrivera/rust,GBGamer/rust,aepsil0n/rust,emk/rust,barosl/rust,bombless/rust,aidancully/rust,mahkoh/rust,dwillmer/rust,vhbit/rust,barosl/rust,P1start/rust,mdinger/rust,miniupnp/rust,rohitjoshi/rust,zaeleus/rust,rprichard/rust,TheNeikos/rust,nwin/rust,mihneadb/rust,aneeshusa/rust,krzysz00/rust,AerialX/rust,P1start/rust,quornian/rust,nwin/rust,AerialX/rust-rt-minimal,zachwick/rust,seanrivera/rust,dwillmer/rust,pelmers/rust,0x73/rust,0x73/rust,AerialX/rust,bombless/rust,kwantam/rust,XMPPwocky/rust,miniupnp/rust,mdinger/rust,mvdnes/rust,jbclements/rust,nham/rust,gifnksm/rust,P1start/rust,gifnksm/rust,bombless/rust,quornian/rust,jroesch/rust,reem/rust,jroesch/rust,miniupnp/rust,richo/rust,mahkoh/rust,philyoon/rust,ktossell/rust,gifnksm/rust,robertg/rust,aidancully/rust,barosl/rust,aepsil0n/rust,untitaker/rust,P1start/rust,untitaker/rust,aepsil0n/rust,graydon/rust,dinfuehr/rust,AerialX/rust,nwin/rust,reem/rust,zachwick/rust,XMPPwocky/rust,avdi/rust,jashank/rust,krzysz00/rust,jashank/rust,ktossell/rust,zachwick/rust,kwantam/rust,robertg/rust,XMPPwocky/rust,kimroen/rust,dwillmer/rust,zubron/rust,XMPPwocky/rust,avdi/rust,vhbit/rust,jashank/rust,victorvde/rust,erickt/rust,KokaKiwi/rust,victorvde/rust,erickt/rust,jroesch/rust,philyoon/rust,mahkoh/rust,quornian/rust,pshc/rust,mihneadb/rust,pshc/rust,ebfull/rust,gifnksm/rust,omasanori/rust,nham/rust,aidancully/rust,seanrivera/rust,rohitjoshi/rust,ruud-v-a/rust,vhbit/rust,aneeshusa/rust,dinfuehr/rust,hauleth/rust,jbclements/rust,AerialX/rust-rt-minimal,quornian/rust,miniupnp/rust,robertg/rust,pshc/rust,pshc/rust,erickt/rust,miniupnp/rust,untitaker/rust,defuz/rust,nham/rust,nwin/rust,aepsil0n/rust,vhbit/rust,AerialX/rust,jbclements/rust,ktossell/rust,ruud-v-a/rust,0x73/rust,richo/rust,nwin/rust,l0kod/rust,emk/rust,mahkoh/rust,jashank/rust,omasanori/rust,l0kod/rust,ejjeong/rust,omasanori/rust,sae-bom/rust,jroesch/rust,kimroen/rust,aneeshusa/rust,victorvde/rust,kwantam/rust,bombless/rust-docs-chinese,jashank/rust,mahkoh/rust,quornian/rust,graydon/rust,graydon/rust,l0kod/rust,zubron/rust,bombless/rust,miniupnp/rust,barosl/rust,graydon/rust,erickt/rust,GBGamer/rust,jbclements/rust,andars/rust,mdinger/rust,ktossell/rust