Merge remote-tracking branch 'upstream/master' into md-link

Author: ordovicia

.travis.yml

@@ -7,7 +7,7 @@ before_install:
   - git --version
 script:
   - rev=$(git rev-parse --short HEAD)
-  - (cargo install mdbook --git https://github.com/azerupi/mdBook.git --force || true)
+  - (cargo install mdbook --vers 0.0.26 --force || true)
   - ./generate-book.sh
   - cd book
   - git init

text/2052-epochs.md

@@ -1,7 +1,7 @@
 - Feature Name: N/A
 - Start Date: 2017-06-26
 - RFC PR: [rust-lang/rfcs#2052](https://github.com/rust-lang/rfcs/pull/2052)
-- Rust Issue: N/A
+- Rust Issue: [rust-lang/rust#44581](https://github.com/rust-lang/rust/issues/44581)
 
 # Summary
 [summary]: #summary

text/2089-implied-bounds.md

@@ -67,7 +67,7 @@ However what we know is that if `Cow<'a, B>` is well-formed, then `B` *has* to i
 
 Currently, impls and functions have to prove that their arguments are well-formed. Under this proposal, they would *assume* that their arguments are well-formed, leaving the responsibility for proving well-formedness to the caller. Hence we would be able to drop the `B: ToOwned` bounds in the previous examples.
 
-Beside reducing repeated constraints, it would also provide a clearer separation between what bounds a type needs so that it is is well-formed, and what additional bounds an `fn` or an `impl` actually needs:
+Beside reducing repeated constraints, it would also provide a clearer separation between what bounds a type needs so that it is well-formed, and what additional bounds an `fn` or an `impl` actually needs:
 
 ```rust
 struct Set<K> where K: Hash + Eq { ... }
@@ -95,7 +95,7 @@ pub fn debug_struct_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>, name: &str) ->
 ```
 This RFC proposes to extend this sort of logic beyond these special cases and use it uniformly for both trait bounds and lifetime bounds.
 
-¹Actually only a few types in the standard library have bounds, for example `HashSet<T>` does not have a `T: Hash + Eq` on the type declaration, but on the impl declaration rather. Wether we should prefer bounds on types or on impls is related, but beyond the scope of this RFC.
+¹Actually only a few types in the standard library have bounds, for example `HashSet<T>` does not have a `T: Hash + Eq` on the type declaration, but on the impl declaration rather. Whether we should prefer bounds on types or on impls is related, but beyond the scope of this RFC.
 
 ## Traits