imported a reworked version of BTL (Benchmark for Templated Libraries).

the modifications to initial code follow:
* changed build system from plain makefiles to cmake
* added eigen2 (4 versions: vec/novec and fixed/dynamic), GMM++, MTL4 interfaces
* added "transposed matrix * vector" product action
* updated blitz interface to use condensed products instead of hand coded loops
* removed some deprecated interfaces
* changed default storage order to column major for all libraries
* new generic bench timer strategy which is supposed to be more accurate
* various code clean-up

bench/btl/data/mk_new_gnuplot.sh

@@ -0,0 +1,45 @@
+#! /bin/bash
+WHAT=$1
+DIR=$2
+cat ../${WHAT}.hh > ${WHAT}.gnuplot
+
+DATA_FILE=`cat ../order_lib`
+
+echo plot \\ >> $WHAT.gnuplot
+
+for FILE in $DATA_FILE
+do
+    LAST=$FILE
+done
+
+
+for FILE in $DATA_FILE
+do
+     if [ $FILE != $LAST ]
+     then
+	echo "'"$FILE"'" ",\\" >>  $WHAT.gnuplot
+     fi
+done
+echo "'"$LAST"'" >>  $WHAT.gnuplot
+
+echo set term postscript color >> $WHAT.gnuplot
+echo set output "'"../${DIR}/$WHAT.ps"'" >> $WHAT.gnuplot
+#echo set term pbm color >> $WHAT.gnuplot
+#echo set output "'"../${DIR}/$WHAT.ppm"'" >> $WHAT.gnuplot
+echo plot \\ >> $WHAT.gnuplot
+for FILE in $DATA_FILE
+do
+     if [ $FILE != $LAST ]
+     then
+	echo "'"$FILE"'" ",\\" >>  $WHAT.gnuplot
+     fi
+done
+echo "'"$LAST"'" >>  $WHAT.gnuplot
+
+gnuplot -persist < $WHAT.gnuplot
+
+rm $WHAT.gnuplot
+
+
+
+