Feature/statistics ui

prevent a bug

improved log viewer

1. WrapTextTrigger -> wrapTextTrigger
2. WrapTextTriggerLock -> wrapTextTriggerLock
3. TopMostTrigger -> topMostTrigger
4. TopMostTriggerLock -> topMostTriggerLock
5. ShowToolbarTrigger -> toolbarTrigger

1. add menu items for `clear logs`, `change fonts`, `wrap text` and `top most` functions.
2. hide toolbar default. but you can trigger it out by menu.

Restart twice, when click Ok button on Edit Servers window

- Add an option for checking updates
- download updates automatically

follow with 5ae4df94e4

bump 2.5.8

Update GFWList URL

Release/2.5.7

no repeat random number generator by GangZhuo

The stock code use class Random to generate IV, the Random is pseudo random number generator. The IV maybe repeat, this will cause shadowsocks-libev closed the sockets with the error message 'invalid password or cipher'. Reference https://github.com/shadowsocks/shadowsocks-libev/issues/389

Solution is use class RNGCryptoServiceProvider to generate IV, of course it's lower performance, but a little bit.