massive refactoring to switch from camelCase to snake_case:

historically, Libervia (SàT before) was using camelCase as allowed by PEP8 when using a
pre-PEP8 code, to use the same coding style as in Twisted.

However, snake_case is more readable and it's better to follow PEP8 best practices, so it
has been decided to move on full snake_case. Because Libervia has a huge codebase, this
ended with a ugly mix of camelCase and snake_case.

To fix that, this patch does a big refactoring by renaming every function and method
(including bridge) that are not coming from Twisted or Wokkel, to use fully snake_case.

This is a massive change, and may result in some bugs.

sat/plugins/plugin_tickets_import_bugzilla.py

@@ -125,13 +125,13 @@ class BugzillaParser(object):
 
 class BugzillaImport(object):
     def __init__(self, host):
-        log.info(_("Bugilla Import plugin initialization"))
+        log.info(_("Bugilla import plugin initialization"))
         self.host = host
         host.plugins["TICKETS_IMPORT"].register(
-            "bugzilla", self.Import, SHORT_DESC, LONG_DESC
+            "bugzilla", self.import_, SHORT_DESC, LONG_DESC
         )
 
-    def Import(self, client, location, options=None):
+    def import_(self, client, location, options=None):
         if not os.path.isabs(location):
             raise exceptions.DataError(
                 "An absolute path to XML data need to be given as location"