Port the open-source project obexftp to the Android platform to implement the Bluetooth FTP Function

On the Android platform, Bluetooth file transmission only implements one OPP function. In the past, I implemented the Bluetooth FTP function in Android development, mainly by porting open-source projects and modifying several bugs, since I have no longer worked for the original company for more than a year, I am planning to release this implementation process, and I am also planning to develop the Bluetooth pan function, which is not available in Google's Android, I wrote it here first. I haven't developed it for a long time. I have time to sort it out later. If you are interested in it, you can leave a letter for us to discuss with each other.