Unifi-python-api

- added spaces throughout Client.php following PSR-2 guidelines
- changed checks to prevent 0 (zero), and "0" values from being submitted to the API for routes where this can have negative side effects

- merged PR 28, thanks go to jamieaitken
- further cleanup to follow PSR-2 as much as possible
- added stat_5minutes_gateway(), stat_hourly_gateway() and stat_daily_gateway() methods
- added changes to ensure we always use lowercase MAC addresses in API routes and payload (we have seen several issues with controllers ignoring uppercase MAC addresses)

- added stat_speedtest_results() method/function to collect results from scheduled speed tests
- added list_backups() method/function to list auto backups

updated comments for stats-related methods/function to make clear start/end values must be provided in milliseconds
changed use of objects as payload input for json_encode, to associative arrays for consistency
added functions/methods for firewall groups: list_firewallgroups(), create_firewallgroup(), edit_firewallgroup(), delete_firewallgroup()
added checks for required boolean parameters

merged PR by Warafux:
added edit_client_fixedip() function/method
added optional parameter to list_networkconf() to fetch config details for a specific network

clean up after resolving merge conflicts

added user/client device stats methods/functions:
stat_5minutes_user()
stat_hourly_user()
stat_daily_user()
added example to demonstrate use of these new functions

added unblock_list.php and block_list.php examples, contributed by malcolmcif ( 20 )
added create_user() method/function
added forget_sta() method/function which is supported on controller version 5.9.* and higher