支持获取自定义的 Agent 启动参数

[dadiyang]

1. 支持获取自定义的 Agent 启动参数 获取自定义的 Agent 启动参数 #164
2. Advice添加获取目标类加载器的快捷方法 Advice中获取ClassLoader很麻烦 #161

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[codecov-io]

Codecov Report

Merging #163 into develop-for-20190410 will decrease coverage by 0.09%.
The diff coverage is 0%.

@@                   Coverage Diff                   @@
##           develop-for-20190410     #163     +/-   ##
=======================================================
- Coverage                 43.03%   42.94%   -0.1%     
=======================================================
  Files                        98       98             
  Lines                      4136     4147     +11     
  Branches                    667      672      +5     
=======================================================
+ Hits                       1780     1781      +1     
- Misses                     2174     2185     +11     
+ Partials                    182      181      -1

Impacted Files	Coverage Δ
...a/com/alibaba/jvm/sandbox/agent/AgentLauncher.java	0% <0%> (ø)	⬆️
...va/com/alibaba/jvm/sandbox/core/CoreConfigure.java	50% <0%> (-1.48%)	⬇️
...m/alibaba/jvm/sandbox/api/listener/ext/Advice.java	38.18% <0%> (-1.11%)	⬇️
...m/sandbox/core/manager/impl/DefaultConfigInfo.java	0% <0%> (ø)	⬆️
...a/jvm/sandbox/api/listener/ext/AdviceListener.java	20% <0%> (ø)	⬆️
...andbox/api/listener/ext/AdviceAdapterListener.java	43.66% <0%> (ø)	⬆️
...jvm/sandbox/core/server/jetty/JettyCoreServer.java	0% <0%> (ø)	⬆️
.../sandbox/core/util/matcher/UnsupportedMatcher.java	0% <0%> (ø)	⬆️
... and 3 more

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[dadiyang]

通过一个 map 来存放，最后再统一序列化，这样代码更加清晰，更易于维护。

[dadiyang]

提供两个获取启动参数的方法，一个是获取单个的，一个是获取全部的。