Breakout shipBrowser into individual class files

gui/builtinShipBrowser/pfBitmapButton.py

@@ -0,0 +1,14 @@
+import wx
+from wx.lib.buttons import GenBitmapButton
+
+
+class PFGenBitmapButton(GenBitmapButton):
+    def __init__(self, parent, id, bitmap, pos, size, style):
+        GenBitmapButton.__init__(self, parent, id, bitmap, pos, size, style)
+        self.bgcolor = wx.Brush(wx.WHITE)
+
+    def SetBackgroundColour(self, color):
+        self.bgcolor = wx.Brush(color)
+
+    def GetBackgroundBrush(self, dc):
+        return self.bgcolor