instances show the window of the primary psensor instance and
exits.
** many code quality improvements.
+** psensor: added --new-instance option to allow the creation of
+ multiple instances of Psensor.
+** psensor: added the degree sign before the temperature symbols.
+** psensor: alarm limit edition using the temperature unit set in the
+ global pref.
+** psensor: improved notification (added psensor icon and value of the
+ sensor).
* v0.6.2.17