Merge remote-tracking branch 'mysql2cn/master'
adding 15.0_High_Availability_and_Scalability.md; first commit; test
updating TOC in 15.0
adding 15.1 through 15.5
adding images for 15.0 to 15.5
添加使用说明
美化代码显示
再次测试
删除测试资料
完成5.1.5前言

完成5.1.5前言，尚未核对。
改了一些格式
add chapter 4.6
14.1 提交
Merge remote-tracking branch 'mysql2cn/master'
Update 4.6.2_myisamftdump—Display_Full-Text_Index_information.md
Update 4.6.2_myisamftdump—Display_Full-Text_Index_information.md
Update 4.6.2_myisamftdump—Display_Full-Text_Index_information.md
Update 4.6.2_myisamftdump—Display_Full-Text_Index_information.md
Update 4.6.2_myisamftdump—Display_Full-Text_Index_information.md
Update 4.6.2_myisamftdump—Display_Full-Text_Index_information.md