fix polygon and polyline description

Author: sprocketc

src/renderer/element/impl/shape/polygon.cljs

@@ -8,8 +8,9 @@
 (defmethod element.hierarchy/properties :polygon
   []
   {:icon "polygon"
-   :description "The <polyline> SVG element is an SVG basic shape that creates
-                 straight lines connecting several points."
+   :description "The <polygon> SVG element defines a closed shape consisting of
+                 a set of connected straight line segments. The last point is
+                 connected to the first point."
    :attrs [:stroke-width
            :fill
            :stroke

src/renderer/element/impl/shape/polyline.cljs

@@ -9,13 +9,15 @@
   []
   {:icon "polyline"
    :description "The <polyline> SVG element is an SVG basic shape that creates
-                 straight lines connecting several points."
+                 straight lines connecting several points. Typically a polyline
+                 is used to create open shapes as the last point doesn't have to
+                 be connected to the first point."
    :attrs [:stroke-width
            :fill
            :stroke
+           :stroke-linejoin
            :stroke-linecap
            :stroke-dasharray
-           :stroke-linejoin
            :opacity]})
 
 (defmethod element.hierarchy/path :polyline