Build system cleanup, initial piece of automatic build test system (thanks xachen)

minor mod- I kept build.sh in the root dir for now.

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@560 d0543943-73ff-0310-b7d9-9358b9ac24b2

build/checkversion.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+
+if [ ! -z $1 ] ; then
+    if [ $1 = force ] ; then
+	rm -f .version
+    fi
+fi
+
+force=0
+version=`svnversion . -n || echo hacked`
+oldversion=`cat .version 2>/dev/null || echo "0"`
+grep "@SVN_VERSION@" src/include/switch_version.h && force=1
+
+if [ $oldversion != $version ] || [ $force = 1 ] ; then
+    cat src/include/switch_version.h.in | sed "s/@SVN_VERSION@/$version/g" > src/include/switch_version.h
+    echo $version > .version
+    make modclean
+fi
+
+
+