修复会出现停止解析的问题，已应用在项目中，暂未发现有问题

[davidgerka]

当富文本有很多图片时，有可能会出现停止解析的问题，原因是synchronized的锁嵌套导致出现了死锁现象，改用信号量Semaphore来实现功能。
还解决了多图片时会偶尔出现图片显示数量不全的问题，比如富文本有6张图片，结果才显示了4张，其他两张只显示一个占位符。
引用的disklrucache库有点问题，看源代码已经有pull requests了，所以直接引入该代码了

[pengjunhong]

有问题，最后一张图片显示不了。
static final String test = "<div id="kindPicture-10086004108929">\r\n\t\t\t \t\t

<img alt="PC-3.jpg" src="https://res.vmallres.com/pimages/detailImg/2020/04/07/95B7BE58F510308F404A32BF170747113A3A7035997B5F11.jpg\">

<a href="https://www.vmall.com/product/10086341564703.html\"><img alt="第二版 pc.jpg" src="https://res.vmallres.com/pimages/detailImg/2020/04/04/42E92F9C6EF729398B98A12CF9857C80790B1A1581618AC0.jpg\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/1A2E1A639CA575209D260DD9E2849688BFDAD6199465903D.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/83F41D3B873B60372A2D20285F922E3E55B6E6ACC1D331CB.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/9151F35663000DBA01309DC5CD473525E1E359EDAC197231.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/88C5563E0C7CAA79DF6DE8C65461B30A03482289D83DCCDF.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/C5DEB0058A15E88CF3D9DDF73118845C5AEED1CECA7AF410.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/B6ABDC958393C7E6405DD14CBDDDBD15C2D1ED32352C4F7E.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/20CFDB80765327325FF8F7646FA060AA75E635E025DBF31C.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/A42F01DB2BBA4199102BC92EF55D1A3AD0B48CA3F6BB2946.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/64A83DCF4113660120C59ED1CBF3385E1C7A8AB9A3762C52.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/F3F74BA9E28D8A59FB8DEC02A274F64B50C9C9E0889B5F88.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/FDF571248D4B18856AAA060A7BBFF5A7AB208C486FE9E6C8.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/4C284126AD074B402472120547F41AC573955F09FE072028.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/C0780CABAF8E5A53BECB742D26CE12D03FE9380AD82D8B46.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/A9C5E5D380B807301EC643EEF4323F56C2511E31B54A46DA.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/BBA7C2A82C1FDE270DAB83B65F889D12BA64B8B63D9E60A2.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/FB82D70D4B1062963D94DFE25BA56671B69FF37205526440.gif\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/09E958B79C4583D05715310580A700CFB0F7DDEBC9DCD3C8.gif\">

<img alt="开箱图 1920.jpg" src="https://res.vmallres.com/pimages/detailImg/2020/04/08/0D5CCC3BAB1B16D442AAA6D3A9AFDF22280D7AC884289474.jpg\">

<img style="" src="https://res.vmallres.com/pimages/detailImg/2020/03/30/ABD0AA86D2A28E4F3482174B05F1B2A77EBDF811D7602FA2.jpg\">

\r\n\t\t\t \t";