added headers

src/circular_sector.scad

@@ -1,3 +1,16 @@
+/**
+* circular_sector.scad
+*
+* Create a circular sector. You can pass a 2 element vector to define the central angle. It provides a fn parameter consistent with the $fn parameter of the circle module.
+* 
+* @copyright Justin Lin, 2017
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib-circular_sector.html
+*
+**/
+
+
 module circular_sector(radius, angles, fn = 24) {
     r = radius / cos(180 / fn);
     step = -360 / fn;

src/line2d.scad

@@ -1,3 +1,15 @@
+/**
+* line2d.scad
+*
+* Creates a line from two points.
+* 
+* @copyright Justin Lin, 2017
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib-line2d.html
+*
+**/
+
 // The end-cap style
 CAP_BUTT = 0;
 CAP_SQUARE = 1;

src/polyline2d.scad

@@ -1,3 +1,15 @@
+/**
+* polyline2d.scad
+*
+* Creates a polyline from a list of x, y coordinates. It depends on the line2d module so you have to include line2d.scad.
+* 
+* @copyright Justin Lin, 2017
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib-polyline2d.html
+*
+**/
+
 module polyline2d(points, width, startingStyle = CAP_SQUARE, endingStyle = CAP_SQUARE, round_fn = 24) {
     module line_segment(index) {
 	    styles = index == 1 ? [startingStyle, CAP_ROUND] : (