implement clipboard on OSX, fix hex and rob sliders on picker

src/util.cpp

@@ -485,7 +485,7 @@ glm::vec4 rand_color()
     return { r, g, b, 1.f };
 }
 
-glm::vec3 convert_long_rgb(unsigned long hex)
+glm::vec3 convert_long_rgb(uint32_t hex)
 {
     uint8_t b = (hex >> 0) & 0xFF;
     uint8_t g = (hex >> 8) & 0xFF;
@@ -493,7 +493,7 @@ glm::vec3 convert_long_rgb(unsigned long hex)
     return glm::vec3(r, g, b) / 255.f;
 }
 
-unsigned long convert_rgb_long(glm::vec3 rgb)
+uint32_t convert_rgb_long(glm::vec3 rgb)
 {
     uint8_t r = (uint8_t)(rgb.r * 255.f);
     uint8_t g = (uint8_t)(rgb.g * 255.f);