Update cargo, books

Cargo.lock

@@ -307,7 +307,7 @@ dependencies = [
  "glob",
  "hex 0.4.0",
  "home",
- "humantime",
+ "humantime 2.0.0",
  "ignore",
  "im-rc",
  "jobserver",
@@ -1013,7 +1013,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aafcde04e90a5226a6443b7aabdb016ba2f8307c847d524724bd9b346dd1a2d3"
 dependencies = [
  "atty",
- "humantime",
+ "humantime 1.3.0",
  "log",
  "regex",
  "termcolor",
@@ -1026,7 +1026,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "44533bbbb3bb3c1fa17d9f2e4e38bbbaf8396ba82193c4cb1b6445d711445d36"
 dependencies = [
  "atty",
- "humantime",
+ "humantime 1.3.0",
  "log",
  "regex",
  "termcolor",
@@ -1454,6 +1454,12 @@ dependencies = [
  "quick-error",
 ]
 
+[[package]]
+name = "humantime"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9b6c53306532d3c8e8087b44e6580e10db51a023cf9b433cea2ac38066b92da"
+
 [[package]]
 name = "hyper"
 version = "0.12.31"
@@ -2647,7 +2653,7 @@ dependencies = [
  "clap",
  "derive_more",
  "env_logger 0.6.2",
- "humantime",
+ "humantime 1.3.0",
  "lazy_static 1.3.0",
  "log",
  "rls-span",

src/doc/book

@@ -1 +1 @@
-Subproject commit 5c5cfd2e94cd42632798d9bd3d1116133e128ac9
+Subproject commit 87dd6843678575f8dda962f239d14ef4be14b352

src/doc/embedded-book

@@ -1 +1 @@
-Subproject commit 9493b7d4dc97eda439bd8780f05ad7b234cd1cd7
+Subproject commit 4d78994915af1bde9a95c04a8c27d8dca066232a

src/doc/reference

@@ -1 +1 @@
-Subproject commit e1157538e86d83df0cf95d5e33bd943f80d0248f
+Subproject commit 11e893fc1357bc688418ddf1087c2b7aa25d154d

src/doc/rust-by-example

@@ -1 +1 @@
-Subproject commit 1d59403cb5269c190cc52a95584ecc280345495a
+Subproject commit 1c2bd024d13f8011307e13386cf1fea2180352b5

src/tools/cargo

@@ -1 +1 @@
-Subproject commit ad3dbe10e1e654fb1f032a5dd9481d7cbaa00d65
+Subproject commit f6449ba236db31995255ac5e4cad4ab88296a7c6