V2ex-daily-mission

- add:
- now you can init the config file with subcommand `init`
- add tests
- fix:
- short version parameter: "-v" --> "-V"
- use abspath for log directory

- add:
- add windows support(tested on win thin pc)
- add '--config' option, you can specify the config file now
- change:
- break change, the main command to get money: v2ex -> v2ex sign
- rewrite with click
- depecate: don't need 'count' in your config file any more, default to 5
- drop 2.6 support, although it may works

- add:
- python 3.x support

- fix:
- fix importError when install v2ex_daily_mission

- change:
- break change, change the command: v2ex_daily_mission -> v2ex

- fix:
- fix the problem that fail to get money, fix 16