Added src-libs subdirectory for keeping source code to extra libs. These

are things that are needed, but that many systems already have packages
available to install, and many users may have versions of these already
installed to support other projects.  So rather than build and install by
default with the main SimGear build/install, these are kept separate so that
those users that don't have them already installed can build and install
them separately.

Makefile.am

@@ -5,11 +5,9 @@ EXTRA_DIST = \
 	README.metakit \
 	README.zlib \
 	SimGear.dsp \
-	SimGear.dsw \
-	metakit-2.4.2-32.tar.gz \
-	zlib-1.1.4.tar.gz
+	SimGear.dsw
 
-SUBDIRS	= simgear
+SUBDIRS	= src-libs simgear
 
 #
 # Rule to build RPM distribution package

configure.in

@@ -292,6 +292,7 @@ fi
 dnl Check for system installed metakit
 AC_CHECK_HEADER(mk4.h)
 if test "x$ac_cv_header_mk4_h" != "xyes"; then
+    echo 
     echo "Metakit not found, you will need to install this first."
     echo "Please read the README.metakit for more information."
     exit
@@ -303,11 +304,24 @@ dnl Specify if we want logging (testing build) or not (release build)
 dnl Check for system installed zlib
 AC_CHECK_HEADER(zlib.h)
 if test "x$ac_cv_header_zlib_h" != "xyes"; then
+    echo 
     echo "zlib not found, you will need to install this first."
     echo "Please read the README.zlib for more information."
     exit
 fi
 
+AC_LANG_SAVE
+AC_LANG_CPLUSPLUS
+dnl Check for installed boost headers
+AC_CHECK_HEADER(boost/config.hpp)
+if test "x$ac_cv_header_boost_config_hpp" != "xyes"; then
+    echo 
+    echo "Boost not found, you will need to install this first."
+    echo "Please read the README.boost for more information."
+    exit
+fi
+AC_LANG_RESTORE
+
 dnl Checks for header files.
 AC_HEADER_STDC
 AC_CHECK_HEADERS( \
@@ -335,6 +349,7 @@ AM_CONFIG_HEADER(simgear/simgear_config.h)
 AC_OUTPUT( \
 	Makefile \
 	SimGear.spec \
+	src-libs/Makefile \
 	simgear/Makefile \
 	simgear/version.h \
 	simgear/bucket/Makefile \