auto merge of #11190 : eliovir/rust/patch-3, r=alexcrichton

#[ author = "Jane Doe" ]; raises "warning: unknown crate attribute"
replace `pkgid` by `crate_id`
add `comment`

doc/rust.md

@@ -615,7 +615,7 @@ the behavior of the compiler.
 // Additional metadata attributes
 #[ desc = "Project X" ];
 #[ license = "BSD" ];
-#[ author = "Jane Doe" ];
+#[ comment = "This is a comment on Project X." ];
 
 // Specify the output type
 #[ crate_type = "lib" ];