fix README.md
fix output of surroundings
binary STL export
simplify widget structure
add url options: width, height, popup and hidebutton
external style sheet
fix url of popup window
STLExporter: fix rotation
STLExport: export sides
new object type: Pipe and Cone (line)
fix centroid height output
label: height settings
place extruded polygons on centroid height
small fixes
label style update
fix error that occurs after upgrading to v.0.7 (new object module fails to be loaded)
add url parameters: camera position, target position and camera up-direction
fix typos
add CHANGELOG.md
v.0.7.1