eolian: move efl eo files over to the new ctor syntax

eolian_cxx/colourable.eo

@@ -4,11 +4,11 @@ class Colourable (Eo.Base)
     legacy_prefix: legacy;
     data: Colourable_Data;
     methods {
-        constructor @constructor {
+        constructor {
             /*@ Default constructor. */
             legacy: null;
         }
-        rgb_composite_constructor @constructor {
+        rgb_composite_constructor {
             /*@ Composite RGB Constructor. */
             legacy: null;
             params {
@@ -17,7 +17,7 @@ class Colourable (Eo.Base)
                 @in int b; /*@ The blue component. */
                }
         }
-        rgb_24bits_constructor @constructor {
+        rgb_24bits_constructor {
             /*@ RGB Constructor. */
             legacy: null;
             params {
@@ -59,6 +59,11 @@ class Colourable (Eo.Base)
             }
         }
     }
+    constructors {
+        .constructor;
+        .rgb_composite_constructor;
+        .rgb_24bits_constructor;
+    }
     events {
         colour_changed: int;
     }

eolian_cxx/colourablesquare.eo

@@ -3,7 +3,7 @@ class ColourableSquare (Colourable)
     legacy_prefix: legacy;
     data: ColourableSquare_Data;
     properties {
-       size_constructor @constructor {
+       size_constructor {
            legacy: null;
            params {
               @in int size;
@@ -24,4 +24,7 @@ class ColourableSquare (Colourable)
     methods {
         size_print { /*@ Show the square. */ }
     }
+    constructors {
+        .size_constructor;
+    }
 }