GSMTAP: --gsmtap-bind to listen beyond loopback (containers)

A container's 127.0.0.1 is its own loopback, so a GSMTAP feed sent to the
container's bridge address never reached the listener: it was hard-bound to
127.0.0.1.

- `simtrace-analyser-server --gsmtap-bind ADDR` (default 127.0.0.1) is passed
  through GsmtapListener to GsmtapReceiver (whose bind_ip already existed),
  including the receiver re-created by a start() after close.  The startup
  banner prints the effective bind address next to the port.
- READMEs (EN/RU) document the option, naming the container case.
- tests: the listener forwards the address on construction and on start(),
  binds 0.0.0.0, and keeps the loopback default.

Verified end-to-end: with --gsmtap-bind 0.0.0.0 the socket listens on
0.0.0.0:14732 and an ATR + APDU sent to 127.0.0.1:14732 landed in the capture
session (2 messages); without the flag it listens on 127.0.0.1.
557 Python + 80 Node tests.

simtrace_analyser/capture.py

@@ -39,15 +39,17 @@ def gsmtap_msg_type(sub_type):
 
 
 class GsmtapListener:
-    def __init__(self, bind_port=4729):
+    def __init__(self, bind_port=4729, bind_ip='127.0.0.1'):
         self._bind_port = bind_port
-        self._receiver = GsmtapReceiver(bind_port=bind_port)
+        self._bind_ip = bind_ip
+        self._receiver = GsmtapReceiver(bind_ip=bind_ip, bind_port=bind_port)
         self._running = False
         self._dropped = 0
 
     def start(self):
         if getattr(self._receiver, '_closed', False):
-            self._receiver = GsmtapReceiver(bind_port=self._bind_port)
+            self._receiver = GsmtapReceiver(bind_ip=self._bind_ip,
+                                            bind_port=self._bind_port)
         self._running = True
         self._dropped = 0