Add Regional_Indicator support from PropList.txt.

src/include/ucd/ucd.h

 #define UCD_PROPERTY_EMOJI_PRESENTATION                 0x0000000400000000ull /**< @brief Emoji_Presentation */
 #define UCD_PROPERTY_EMOJI_MODIFIER                     0x0000000800000000ull /**< @brief Emoji_Modifier */
 #define UCD_PROPERTY_EMOJI_MODIFIER_BASE                0x0000001000000000ull /**< @brief Emoji_Modifier_Base */
+#define UCD_PROPERTY_REGIONAL_INDICATOR                 0x0000002000000000ull /**< @brief Regional_Indicator */
 
 /** @brief Return the properties of the specified codepoint.
  *
 		Emoji_Presentation = UCD_PROPERTY_EMOJI_PRESENTATION, /**< @brief Emoji_Presentation */
 		Emoji_Modifier = UCD_PROPERTY_EMOJI_MODIFIER, /**< @brief Emoji_Modifier */
 		Emoji_Modifier_Base = UCD_PROPERTY_EMOJI_MODIFIER_BASE, /**< @brief Emoji_Modifier_Base */
+		Regional_Indicator = UCD_PROPERTY_REGIONAL_INDICATOR, /**< @brief Regional_Indicator */
 	};
 
 	/** @brief Return the properties of the specified codepoint.

src/proplist.c

 		if (c >= 0x01F170 && c <= 0x01F189) return UCD_PROPERTY_OTHER_ALPHABETIC | UCD_PROPERTY_OTHER_UPPERCASE;
 		if (c == 0x01F18E)                  return UCD_PROPERTY_EMOJI | UCD_PROPERTY_EMOJI_PRESENTATION;
 		if (c >= 0x01F191 && c <= 0x01F19A) return UCD_PROPERTY_EMOJI | UCD_PROPERTY_EMOJI_PRESENTATION;
-		if (c >= 0x01F1E6)                  return UCD_PROPERTY_EMOJI | UCD_PROPERTY_EMOJI_PRESENTATION;
+		if (c >= 0x01F1E6)                  return UCD_PROPERTY_EMOJI | UCD_PROPERTY_EMOJI_PRESENTATION | UCD_PROPERTY_REGIONAL_INDICATOR;
 		break;
 	case 0x01F200:
 		if (c == 0x01F201)                  return UCD_PROPERTY_EMOJI | UCD_PROPERTY_EMOJI_PRESENTATION;

tools/printdata.py

 	props += (2 ** 34) * data.get('Emoji_Presentation', 0) # emoji-data
 	props += (2 ** 35) * data.get('Emoji_Modifier', 0) # emoji-data
 	props += (2 ** 36) * data.get('Emoji_Modifier_Base', 0) # emoji-data
+	props += (2 ** 37) * data.get('Regional_Indicator', 0)
 	return props
 
 if __name__ == '__main__':