senseless if removed in configure_email
check if the email configuration file exists before instantiating ConfigParser
iterate directly in pending_users (not in the pending_users.keys() list),
the python way.
typo
email.settings.ini values are now filled with fake values (instead of empty)
and used in "configure_email" function to avoid the use of
general anti-pattern:

if testingflag
    do somethingfake
else
    do somethingreal
no mention of command manager in the user activation email
send_email function created and used
usertips updated
better and more verbose email text body
server 'reset_userdata' function added
Users api tests rewritten to be more like real *unit* tests
(splitted in more classes and test case methods)
added test for the activation email
pending users clean-up more pythonic
(2 list comprehensions -> 8 lines become 3)
minor change: 'send_email' function now returns the Message instance of sent email
(this return is not used for now)
removed tests for the quick signup (without email)
because it isn't a real feature, it's more like a backdoor.
(if need be, just revert this commit)
server constant PASSWORD renamed to PWD
'app.config['TESTING']' become 'app.testing'
style: blank lines
(limited to the code relate with user activation branch)
user creation timestamp added to the user data (and showed by the GET)
'timeout' - unused in the string Template - value removed