fix the gitignore mess: git refuses to ignore already tracked files

.gitignore

@@ -1,2 +1,2 @@
 notes.txt
-authorized_keys
+build/

build.sh

@@ -2,25 +2,12 @@
 
 set -e
 
-absolutize ()
-{
-  if [ ! -d "$1" ]; then
-    echo
-    echo "ERROR: '$1' doesn't exist or not a directory!"
-    kill -INT $$
-  fi
-
-  pushd "$1" >/dev/null
-  echo `pwd`
-  popd >/dev/null
-}
-
 TARGET_ARCHITECTURE=$1
 TARGET_VARIANT=$2
 TARGET_DEVICE=$3
 
 BUILD=`dirname "$0"`"/build/"
-BUILD=`absolutize $BUILD`
+BUILD=`readlink -f $BUILD`
 
 ###
 ### chose a release

build/.gitignore

@@ -1,4 +0,0 @@
-# Ignore everything in this directory
-*
-# Except this file
-!.gitignore

image-extras/common/etc/dropbear/.gitignore

@@ -0,0 +1,3 @@
+# you can put your ssh public key into authorized_keys,
+# but we don't ever want it to be committed to the repo
+authorized_keys

image-extras/common/etc/dropbear/authorized_keys

@@ -1 +0,0 @@
-# this file may contain ssh public keys for passwordless ssh root login