allow sending ASAP and remove any artificial delays

apps/heartbeat/java/src/net/i2p/heartbeat/ClientConfig.java

@@ -358,7 +358,7 @@ public class ClientConfig {
             int sendFreq = getInt(sendFrequencyVal);
             int sendSize = getInt(sendSizeVal);
 
-            if ((duration <= 0) || (statFreq <= 0) || (sendFreq <= 0) || (sendSize <= 0)) {
+            if ((duration <= 0) || (statFreq <= 0) || (sendFreq < 0) || (sendSize <= 0)) {
                 if (_log.shouldLog(Log.WARN)) {
                     _log.warn("Invalid client config: duration [" + statDurationVal + "] stat frequency ["
                               + statFrequencyVal + "] send frequency [" + sendFrequencyVal + "] send size ["
@@ -424,7 +424,7 @@ public class ClientConfig {
      * @return true if it was stored correctly, false if there were errors
      */
     public boolean store(Properties clientConfig, int peerNum) {
-        if ((_peer == null) || (_sendFrequency <= 0) || (_sendSize <= 0) || (_statDuration <= 0)
+        if ((_peer == null) || (_sendFrequency < 0) || (_sendSize <= 0) || (_statDuration <= 0)
             || (_statFrequency <= 0) || (_statFile == null)) { return false; }
 
         String comment = _comment;

apps/heartbeat/java/src/net/i2p/heartbeat/ClientEngine.java

@@ -120,9 +120,12 @@ class ClientEngine {
 
                 _data.cleanup();
 
-                try {
-                    Thread.sleep(1000);
-                } catch (InterruptedException ie) {
+                long timeToWait = nextSend - Clock.getInstance().now();
+                if (timeToWait > 0) {
+                    try {
+                        Thread.sleep(timeToWait);
+                    } catch (InterruptedException ie) {
+                    }
                 }
             }
         }