[StGIT PATCH] diffcol.sh: Use /bin/bash explicitly

[Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>]

Recent Ubuntu uses dash (Debian Almquist Shell; a lightweight POSIX-
compliant shell derived from ash) as /bin/sh by default.  In this case
pager=diffcol.sh doesn't work like this:

> skuribay@ubuntu:~/kernel/linux.git$ stg show
> /home/skuribay/share/stgit/contrib/diffcol.sh: 22: Bad substitution

this is caused by non-bash-compliant /bin/sh.

diffcol.sh is based on Quilt, and Quilt is dependent on bash; Actually
all Quilt scripts use /bin/bash without exceptions.  Then it's good for
diffcol.sh to use /bin/bash.

Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>
---
 contrib/diffcol.sh |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/contrib/diffcol.sh b/contrib/diffcol.sh
index ea9109d..eecc87a 100755
--- a/contrib/diffcol.sh
+++ b/contrib/diffcol.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 # Code copied from Quilt (http://savannah.nongnu.org/projects/quilt)
 #