全面整理项目内容,可读性更佳

*Total -- 1,473.40kb -> 1,184.44kb (19.61%)

/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
/docs/extra-page/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
/docs/big-data/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
/docs/high-concurrency/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
/docs/distributed-system/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
/docs/micro-services/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
/docs/high-availability/images/pdf.png -- 210.49kb -> 169.21kb (19.61%)
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移除冗余文件，激活页面底部导航

*Total -- 1,087.50kb -> 1,083.88kb (0.33%)

/docs/from-readers/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/high-concurrency/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/high-availability/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/extra-page/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/micro-services/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/distributed-system/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/big-data/images/qrcode-for-doocs.jpg -- 65.77kb -> 65.44kb (0.51%)
/docs/from-readers/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/docs/high-availability/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/docs/micro-services/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/docs/high-concurrency/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/docs/extra-page/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/docs/distributed-system/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
/docs/big-data/images/qrcode-for-yanglbme.jpg -- 70.17kb -> 70.05kb (0.17%)
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更新封面，添加联系方式

/docs/high-availability/images/hystrix-circuit-breaker-state-machine.png -- 101.94kb -> 88.25kb (13.43%)
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* Close #99

更新子目录 README 文档说明

* 图片优化
* Issue(#89) 关闭

更新文档描述

*Total -- 370.62kb -> 317.97kb (14.21%)

/images/BRP.jpg -- 8.95kb -> 6.71kb (25.01%)
/docs/high-availability/images/BRP.jpg -- 8.95kb -> 6.71kb (25.01%)
/images/Sentinel-VS-Hystrix.jpg -- 58.11kb -> 48.47kb (16.59%)
/docs/high-availability/images/Sentinel-VS-Hystrix.jpg -- 58.11kb -> 48.47kb (16.59%)
/images/Slow-Start-Preheating-Mode.jpg -- 24.52kb -> 21.10kb (13.94%)
/docs/high-availability/images/Slow-Start-Preheating-Mode.jpg -- 24.52kb -> 21.10kb (13.94%)
/images/Homogenizer-mode.jpg -- 27.65kb -> 24.02kb (13.12%)
/docs/high-availability/images/Homogenizer-mode.jpg -- 27.65kb -> 24.02kb (13.12%)
/images/Sentinel-Dashboard.jpg -- 66.08kb -> 58.68kb (11.2%)
/docs/high-availability/images/Sentinel-Dashboard.jpg -- 66.08kb -> 58.68kb (11.2%)
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Sentinel 和 Hystrix，该如何做技术选型？
本文由 Doocs 开源组织(https://github.com/doocs)整理自阿里巴巴中间件团队，供各位朋友学习了解，鼓励大家使用阿里开源组件。

更新 Hystrix 多个文件描述信息

*Total -- 37.50kb -> 35.56kb (5.18%)

/images/220px-Internet_dog.jpg -- 18.75kb -> 17.78kb (5.18%)
/docs/high-availability/images/220px-Internet_dog.jpg -- 18.75kb -> 17.78kb (5.18%)

基于 timeout 机制为服务接口的调用超时提供安全保护

- Update UUID desc to fix #22
- Rename img to images
- Fix typo

深入线程池隔离与接口限流知识点补充

*Total -- 13.78kb -> 13.28kb (3.66%)

/img/bulkhead-partition.jpg -- 6.89kb -> 6.64kb (3.66%)
/docs/high-availability/img/bulkhead-partition.jpg -- 6.89kb -> 6.64kb (3.66%)

- Update index.html
- Add hystrix-thread-pool-current-limiting.md
- Update hystrix-introduction and circuit-breaker

深入 Hystrix 断路器执行原理

Hystrix 降级机制具体场景演示

- Update request cache
- Update offer.md
- Update title of Advanced-Java

*Total -- 55.49kb -> 25.74kb (53.6%)

/docs/high-availability/img/hystrix-request-cache.png -- 27.74kb -> 12.87kb (53.6%)
/img/hystrix-request-cache.png -- 27.74kb -> 12.87kb (53.6%)

- Update offer page
- Add hystrix-request-cache.md