Add test_properties command to device class

[rytilahti]

This allows simple testing of available properties, their values & the number of properties that can be requested at once.
This is done in two steps:

1. Testing all given properties one by one to see which return non-None/non-empty values
2. Testing all valid values using a single request, and removing items one by one on failures to obtain usable obtain the max_properties value

Example output:

$ miiocli device --ip <addr> --token <token> test_properties power on off usb_on temperature wifi_led foofoo x
Running command test_properties
Testing properties ('power', 'on', 'off', 'usb_on', 'temperature', 'wifi_led', 'foofoo', 'x') for zimi.powerstrip.v2
Testing power.. on <class 'str'>
Testing on.. None
Testing off.. None
Testing usb_on.. None
Testing temperature.. 46.07 <class 'float'>
Testing wifi_led.. off <class 'str'>
Testing foofoo.. None
Testing x.. None
Found 8 valid properties, testing max_properties..
Testing 8 properties at once.. OK for 8 properties

Please copy the results below to your report
Model: zimi.powerstrip.v2
Total responsives: 8
Total non-empty: 3
All non-empty properties:
{'power': 'on', 'temperature': 46.07, 'wifi_led': 'off'}
Max properties: 8
Done

Closes #919

[syssi]

Awesome!

[rytilahti]

Another example from my vacuum that doesn't support properties (nor info), so it shouldn't crash on unexpected replies:

$ miiocli device --ip $MIROBO_IP --token $MIROBO_TOKEN test_properties on off power status
Running command test_properties
WARNING:miio.device:Unable to obtain device model: Unable to request miIO.info from the device
Testing properties ('on', 'off', 'power', 'status') for <unavailable>
Testing on.. ERROR:miio.miioprotocol:Got error when receiving: timed out
WARNING:miio.device:Unable to request on: No response from the device
Testing off.. ERROR:miio.miioprotocol:Got error when receiving: timed out
WARNING:miio.device:Unable to request off: No response from the device
Testing power.. ERROR:miio.miioprotocol:Got error when receiving: timed out
WARNING:miio.device:Unable to request power: No response from the device
Testing status.. ERROR:miio.miioprotocol:Got error when receiving: timed out
WARNING:miio.device:Unable to request status: No response from the device
Found 0 valid properties, testing max_properties..

Please copy the results below to your report
### Results ###
Model: <unavailable>
Total responsives: 0
Total non-empty: 0
All non-empty properties:
{}
Max properties: -1
Done

and yet another from yeelight, which seems to respond with empty strings instead of Nones for invalid properties:

$ miiocli device --ip <addr> --token <token> test_properties power bright ct rgb hue sat color_mode name lan_ctrl save_state foo bar baz dup dap zap
Running command test_properties
Testing properties ('power', 'bright', 'ct', 'rgb', 'hue', 'sat', 'color_mode', 'name', 'lan_ctrl', 'save_state', 'foo', 'bar', 'baz', 'dup', 'dap', 'zap') for yeelink.light.color1
Testing power.. on <class 'str'>
Testing bright.. 99 <class 'str'>
Testing ct.. 4201 <class 'str'>
Testing rgb.. 16711680 <class 'str'>
Testing hue.. 359 <class 'str'>
Testing sat.. 100 <class 'str'>
Testing color_mode.. 2 <class 'str'>
Testing name..  <class 'str'>
Testing lan_ctrl.. 1 <class 'str'>
Testing save_state.. 0 <class 'str'>
Testing foo..  <class 'str'>
Testing bar..  <class 'str'>
Testing baz..  <class 'str'>
Testing dup..  <class 'str'>
Testing dap..  <class 'str'>
Testing zap..  <class 'str'>
Found 16 valid properties, testing max_properties..
Testing 16 properties at once.. OK for 16 properties

Please copy the results below to your report
### Results ###
Model: yeelink.light.color1
Total responsives: 16
Total non-empty: 16
All non-empty properties:
{'bar': '',
 'baz': '',
 'bright': '99',
 'color_mode': '2',
 'ct': '4201',
 'dap': '',
 'dup': '',
 'foo': '',
 'hue': '359',
 'lan_ctrl': '1',
 'name': '',
 'power': 'on',
 'rgb': '16711680',
 'sat': '100',
 'save_state': '0',
 'zap': ''}
Max properties: 16
Done

[syssi]

A very helpful feature. Hopefully with miOT support some day.

[rytilahti]

Adding similar feature to MiotDevice to use an existing JSON description to print out all values could indeed be useful!

[syssi]

Feel free to merge.