Address inconsistent type self.colors returned by Click generating exception in cmd

Author: joswr1ght

libtmux/server.py

@@ -119,6 +119,8 @@ def cmd(self, *args, **kwargs):
         if self.config_file:
             args.insert(0, '-f{0}'.format(self.config_file))
         if self.colors:
+            # Resolve inconsistent type returned by Click
+            self.colors=int(self.colors)
             if self.colors == 256:
                 args.insert(0, '-2')
             elif self.colors == 88: