Fix clone.sh script.

The both git hook scripts are made exectuables.
Also added quotes to as ber bash style guide.

Change-Id: Ic339a76fc0e48e97c73c5136f1707349752bada5
diff --git a/clone.sh b/clone.sh
index 9786af1..5b0cf5a 100755
--- a/clone.sh
+++ b/clone.sh
@@ -4,15 +4,18 @@
 
     function configure_git_repository {
         # Install message hook, and default push arguments.
-        f=$(git rev-parse --git-dir)/hooks/commit-msg
-        mkdir -p $(dirname $f)
-        curl -Lo $f https://gerrit-review.googlesource.com/tools/hooks/commit-msg
+        f="$(git rev-parse --git-dir)/hooks/commit-msg"
+        mkdir -p "$(dirname $f)"
+        curl -Lo "$f" https://gerrit-review.googlesource.com/tools/hooks/commit-msg
+        chmod +x "$f"
+
         # Install pre-push hook.
-        f=$(git rev-parse --git-dir)/hooks/pre-push
-        mkdir -p $(dirname $f)
-        printf "#!/bin/sh\n$1/presubmit.sh" > $f
-        chmod +x $f
-        # Make `git pull`, `pit pull`, and `git rebase` work without args.
+        f="$(git rev-parse --git-dir)/hooks/pre-push"
+        mkdir -p "$(dirname $f)"
+        printf "#!/bin/sh\n$1/presubmit.sh" > "$f"
+        chmod +x "$f"
+
+        # Make `git pull`, `git push`, and `git rebase` work without args.
         git config branch.*.remote origin
         git config remote.origin.push HEAD:refs/for/master
     }