bin: add git and tig wrappers to support -C <dir>

Signed-off-by: Alejandro Mery <amery@geeks.cl>

files/bin/git

@@ -0,0 +1 @@
+../../lib/chdir_usr_bin_wrapper.sh

files/bin/tig

@@ -0,0 +1 @@
+../../lib/chdir_usr_bin_wrapper.sh

lib/chdir_usr_bin_wrapper.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+TOOL="/usr/bin/${0##*/}"
+
+set -e
+if [ $# -ge 2 ]; then
+	if [ "x-C" = "x$1" ]; then
+		cd "$2"
+		shift 2
+	fi
+fi
+exec $TOOL "$@"