refactor parsers; introduce new pocsag parser

owrx/parser.py

@@ -0,0 +1,20 @@
+from abc import ABC, abstractmethod
+from owrx.bands import Bandplan
+
+
+class Parser(ABC):
+    def __init__(self, handler):
+        self.handler = handler
+        self.dial_freq = None
+        self.band = None
+
+    @abstractmethod
+    def parse(self, raw):
+        pass
+
+    def setDialFrequency(self, freq):
+        self.dial_freq = freq
+        self.band = Bandplan.getSharedInstance().findBand(freq)
+
+    def getBand(self):
+        return self.band