added script for downloading training data

datasets/download_traindata.sh

@@ -0,0 +1,74 @@
+#!/bin/bash
+clear
+cat << EOF
+
+================================================================================
+
+
+The train datasets are provided for research purposes only.
+
+Some of the test datasets build upon other publicly available data.
+Make sure to cite the respective original source of the data if you use the 
+provided files for your research.
+
+  * sun3d_train.h5 is based on the SUN3D dataset http://sun3d.cs.princeton.edu/
+
+    J. Xiao, A. Owens, and A. Torralba, “SUN3D: A Database of Big Spaces Reconstructed Using SfM and Object Labels,” in 2013 IEEE International Conference on Computer Vision (ICCV), 2013, pp. 1625–1632.
+
+
+  
+
+  * rgbd_train.h5 is based on the RGBD SLAM benchmark http://vision.in.tum.de/data/datasets/rgbd-dataset (licensed under CC-BY 3.0)
+    
+    J. Sturm, N. Engelhard, F. Endres, W. Burgard, and D. Cremers, “A benchmark for the evaluation of RGB-D SLAM systems,” in 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2012, pp. 573–580.
+
+
+
+  * scenes11_train.h5 uses objects from shapenet https://www.shapenet.org/
+    
+    A. X. Chang et al., “ShapeNet: An Information-Rich 3D Model Repository,” arXiv:1512.03012 [cs], Dec. 2015.
+
+
+
+  * mvs_train.h5 contains the Citywall and Achteck-Turm scenes from MVE (Multi-View Environment) http://www.gcc.tu-darmstadt.de/home/proj/mve/
+    
+    S. Fuhrmann, F. Langguth, and M. Goesele, “MVE: A Multi-view Reconstruction Environment,” in Proceedings of the Eurographics Workshop on Graphics and Cultural Heritage, Aire-la-Ville, Switzerland, Switzerland, 2014, pp. 11–18.
+
+
+
+================================================================================
+
+type Y to start the download.
+
+EOF
+
+read -s -n 1 answer
+if [ "$answer" != "Y" -a "$answer" != "y" ]; then
+	exit 0
+fi
+echo
+
+datasets=(sun3d rgbd mvs scenes11)
+
+OLD_PWD="$PWD"
+DESTINATION=traindata
+mkdir $DESTINATION
+cd $DESTINATION
+
+if [ ! -e "README_traindata" ]; then
+	wget "https://lmb.informatik.uni-freiburg.de/data/demon/traindata/README_traindata"
+fi
+if [ ! -e "traindata.md5" ]; then
+	wget "https://lmb.informatik.uni-freiburg.de/data/demon/traindata/traindata.md5"
+fi
+
+for ds in ${datasets[@]}; do
+	if [ -e "${ds}_train.h5" ]; then
+		echo "${ds}_train.h5 already exists, skipping ${ds}"
+	else
+		wget "https://lmb.informatik.uni-freiburg.de/data/demon/traindata/${ds}_train.tgz"
+		tar -xvf "${ds}_train.tgz"
+	fi
+done
+
+cd "$OLD_PWD"