Use ~/.cql/ directory as default config location.

[laodouya]

1. Change all cmd config param to ~/.cql/config.yaml
2. Config generate will default use ~/.cql/ as well.
3. Driver can reduce client.Init func call if expected using ~/.cql/
4. Update all unit test.
5. Update all README.md
6. Update client example.
7. Compatible with elder usage.
8. Skip compatibility test if branch name contains '/beta_'

[codecov]

Codecov Report

Merging #233 into develop will decrease coverage by 0.27%.
The diff coverage is 40%.

@@             Coverage Diff             @@
##           develop     #233      +/-   ##
===========================================
- Coverage    77.85%   77.57%   -0.28%     
===========================================
  Files          150      150              
  Lines        11914    11931      +17     
===========================================
- Hits          9276     9256      -20     
- Misses        1946     1977      +31     
- Partials       692      698       +6

[codecov]

Codecov Report

Merging #233 into develop will decrease coverage by 0.25%.
The diff coverage is 40%.

@@            Coverage Diff             @@
##           develop    #233      +/-   ##
==========================================
- Coverage    77.85%   77.6%   -0.26%     
==========================================
  Files          150     150              
  Lines        11914   11931      +17     
==========================================
- Hits          9276    9259      -17     
- Misses        1946    1974      +28     
- Partials       692     698       +6

[auxten]

LGTM

[leventeliu]

LGTM.