Specification for try_esp_delay added as code comment.

Author: dok-net

cores/esp8266/coredecls.h

@@ -51,6 +51,10 @@ inline void esp_suspend(T&& blocked) {
     } while (blocked());
 }
 
+// Try to delay for timeout_ms relative to start_ms. Returns false if the delayed task
+// is asynchronously resumed before the timeout is reached.
+// Also returns false if intvl_ms have expired during the active call.
+// Otherwise return true to indicate the timeout_ms have completely expired.
 bool try_esp_delay(const uint32_t start_ms, const uint32_t timeout_ms, const uint32_t intvl_ms);
 
 // This overload of esp_delay() delays for a duration of at most timeout_ms milliseconds.