Improve documentation

icon.h

@@ -5,6 +5,9 @@
 
 namespace QtForkAwesome {
 
+/*!
+ * \brief The Icon enum specifies a ForkAwesome icon for calling QtForkAwesome::Renderer::render().
+ */
 enum class Icon : IconBaseType {
     Invalid, /**< invalid, used by QtForkAwesome::iconFromId() to indicate failure */
 #include "private/icons.h"

utils.h

@@ -8,6 +8,10 @@ QT_FORWARD_DECLARE_CLASS(QString)
 
 namespace QtForkAwesome {
 
+/*!
+ * \brief Returns whether \a icon is not Icon::Invalid.
+ * \remarks Allows one to avoid including `icon.h` just for this check.
+ */
 constexpr bool isIconValid(Icon icon)
 {
     return static_cast<IconBaseType>(icon);