Remove references to deprecated `extern crate "foo" as bar` syntax
This syntax was removed in but references remained in the
grammar, the reference, rustdoc generation, and some auxiliary test
files that don't seem to have been used since
@@ -752,11 +752,10 @@ provided in the `extern_crate_decl`.
The external crate is resolved to a specific `soname` at compile time, and a
runtime linkage requirement to that `soname` is passed to the linker for
loading at runtime. The `soname` is resolved at compile time by scanning the
-compiler's library path and matching the optional `crateid` provided as a
-string literal against the `crateid` attributes that were declared on the
-external crate when it was compiled. If no `crateid` is provided, a default
-`name` attribute is assumed, equal to the `ident` given in the
-`extern_crate_decl`.
+compiler's library path and matching the optional `crateid` provided against
+the `crateid` attributes that were declared on the external crate when it was
+compiled. If no `crateid` is provided, a default `name` attribute is assumed,
+equal to the `ident` given in the `extern_crate_decl`.
Three examples of `extern crate` declarations:
