Moved stream write and stream skip into common

src/TinyGsmCommon.h

@@ -292,6 +292,33 @@ public:
     return TinyGsmIpFromString(getLocalIP());
   }
 
+    /*
+     Utilities
+     */
+
+    template<typename T>
+    void streamWrite(T last) {
+      stream.print(last);
+    }
+
+    template<typename T, typename... Args>
+    void streamWrite(T head, Args... tail) {
+      stream.print(head);
+      streamWrite(tail...);
+    }
+
+    bool streamSkipUntil(const char c, const unsigned long timeout = 1000L) {
+      unsigned long startMillis = millis();
+      while (millis() - startMillis < timeout) {
+        while (millis() - startMillis < timeout && !stream.available()) {
+          TINY_GSM_YIELD();
+        }
+        if (stream.read() == c)
+          return true;
+      }
+      return false;
+    }
+
 public:
   Stream&       stream;
 };