JIMI_DLL 改为 JIMI_API, 移除JIMI_DLL.

Signed-off-by: shines77 <gz_shines@msn.com>
整理了一下代码, 新增fs::FileSystem类

Signed-off-by: shines77 <gz_shines@msn.com>
增加了Object, String等类(仿Java)

Signed-off-by: shines77 <gz_shines@msn.com>