Cargo.toml: Alphabetically sort the dependencies

Change-Id: Ied0bdc5e0c7afdca99cb57f950b62df2ceb1f366
diff --git a/rustc_deps/Cargo.toml b/rustc_deps/Cargo.toml
index 7ef8f63..a08e5ee 100644
--- a/rustc_deps/Cargo.toml
+++ b/rustc_deps/Cargo.toml
@@ -8,6 +8,7 @@
 authors = ["cramertj <cramertj@google.com>"]
 
 [dependencies]
+# Keep this sorted alphabetically, please.
 base64 = "0.9"
 bincode = "1"
 bit-vec = "0.5.0"
@@ -45,17 +46,17 @@
 num-bigint = { version = "0.2", features = ["rand"] }
 owning_ref = "0.4.0"
 parking_lot = "0.6"
-pin-utils = "=0.1.0-alpha.4"
-pretty_assertions = "0.5.1"
 pest = "2.1"
 pest_derive = "2.1"
+pin-utils = "=0.1.0-alpha.4"
+pretty_assertions = "0.5.1"
 proptest = "0.8.7"
 rand = "0.6"
 rand_core = "0.4.0"
 rand_os = "0.1.2"
 rand_xorshift = "0.1.1"
-ring = "0.14"
 regex = "1.0.6"
+ring = "0.14"
 rouille = "3.0.0"
 rust-crypto = "0.2"
 rustc-serialize = "0.3"
@@ -76,8 +77,8 @@
 unicode-segmentation = "1.0"
 unicode-width = "0.1.3"
 untrusted = "0.6.2"
-utf8parse = "0.1"
 url = "1.7.0"
+utf8parse = "0.1"
 valico = "2.4.2"
 void = "1.0.2"
 vte = "0.3"