Auto merge of #289 - jrmuizel:derive, r=jrmuizel

derive(Clone, Copy, Debug) on Line enums

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core-graphics/src/context.rs

@@ -70,6 +70,7 @@ pub enum CGTextDrawingMode {
 }
 
 #[repr(C)]
+#[derive(Clone, Copy, Debug)]
 pub enum CGLineCap {
     CGLineCapButt,
     CGLineCapRound,
@@ -77,6 +78,7 @@ pub enum CGLineCap {
 }
 
 #[repr(C)]
+#[derive(Clone, Copy, Debug)]
 pub enum CGLineJoin {
     CGLineJoinMiter,
     CGLineJoinRound,