Update DBT.java added DBTF_MEDIA and DBTF_NET
Fixed 2 bugs in Win32WindowDemo.java

Added setting dbcc_size before RegisterDeviceNotification.
Create DEV_BROADCAST_DEVICEINTERFACE only when should.
Added extra info (drive letter, change to media in drive or to physical drive, is network drive) for logic drive add/remove.
Update Win32WindowDemo.java

Used DBT.DBTF_MEDIA to replace 1.
Used DBT.DBTF_NET to replace 2.
Update CHANGES.md
Merge pull request #287 from daifei4321/master

Updated Win32WindowDemo.java