Add documentation comments for where to add new protocols using state…

… and cleanup

src/IRremoteESP8266.h

@@ -654,6 +654,8 @@
      DECODE_AMCOR || DECODE_DAIKIN152 || DECODE_MITSUBISHI136 || \
      DECODE_MITSUBISHI112 || DECODE_HITACHI_AC424 || DECODE_HITACHI_AC3 || \
      DECODE_HITACHI_AC344)
+  // Add any DECODE to the above if it uses result->state (see kStateSizeMax)
+  // you might also want to add the protocol to hasACState function
 #define DECODE_AC true  // We need some common infrastructure for decoding A/Cs.
 #else
 #define DECODE_AC false   // We don't need that infrastructure.

src/IRutils.cpp

@@ -139,6 +139,7 @@ String typeToString(const decode_type_t protocol, const bool isRepeat) {
 // Does the given protocol use a complex state as part of the decode?
 bool hasACState(const decode_type_t protocol) {
   switch (protocol) {
+    // This is keept sorted by name
     case AMCOR:
     case ARGO:
     case DAIKIN: