Add a basic tutorial for the tools in depot_tools.

docs/src/make_docs.sh

Index: docs/src/make_docs.sh
diff --git a/docs/src/make_docs.sh b/docs/src/make_docs.sh
index ac8ab42ba9e5707000350722f83684472b6704e2..48143a2e66f77365ec30402b71843a37c6edfee4 100755
--- a/docs/src/make_docs.sh
+++ b/docs/src/make_docs.sh
@@ -130,6 +130,7 @@ do
           echo -n -
         done
         echo
+        cat _${category}_prefix.txt 2> /dev/null || true
         echo
       fi
 
@@ -145,7 +146,7 @@ do
   } > __${category}.txt
 done
 
-JOBS=0
+JOBS=1
 HTML_TARGETS=()
 MAN_TARGETS=()
 for x in *.txt *.css
@@ -155,22 +156,27 @@ do
   then
     echo \'$x\' differs
     cp $x "$TO"
-  fi
-  # Exclude files beginning with _ from the target list. This is useful to have
-  # includable snippet files.
-  if [[ ${x:0:1} != _ && ${x:(-4)} == .txt ]]
-  then
-    HTML_TARGETS+=("${x%%.txt}.html")
-    if [[ ${x:0:3} == git ]]
+    # Exclude files beginning with _ from the target list. This is useful to have

[Ryan Tseng, 2014/04/05 00:51:20]

80 char

[iannucci, 2014/04/05 01:31:13]

Done.

[iannucci, 2014/04/05 01:31:13]

Done.

+    # includable snippet files.
+    if [[ ${x:0:1} != _ && ${x:(-4)} == .txt ]]
     then
-      MAN1_TARGETS+=("${x%%.txt}.1")
-    else
-      MAN7_TARGETS+=("${x%%.txt}.7")
+      HTML_TARGETS+=("${x%%.txt}.html")
+      if [[ ${x:0:3} == git ]]
+      then
+        MAN1_TARGETS+=("${x%%.txt}.1")
+      else
+        MAN7_TARGETS+=("${x%%.txt}.7")
+      fi
+      JOBS=$[$JOBS + 2]
     fi
-    JOBS=$[$JOBS + 2]
   fi
 done
 
+if [[ ${#HTML_TARGETS} == 0 && ${#MAN_TARGETS} == 0 ]]
+then
+  exit
+fi
+
 VER="v$(git rev-parse --short HEAD)"
 if [[ ! -f git/version ]] || ! cmp --silent git/version <(echo "$VER")
 then