Make port reusable between sessions

[jupagose]

Now if last port used is still available, is used this can avoid users the need of transmit "connection info" if need to connet again.

[miroslavpejic85]

Hello @jupagose,

Thank you so much for this PR, but in this way:

1. You can't open multiple simultaneous sessions of P2P Remote Desktop on the same PC.
2. Are you sure that the port you forced and saved in the registry, still always open?
3. The idea is also to make it cross-platform, so writing to the registry is also strictly for Windows OS.

What do you think?

Anyway thank you again and have a good day.

[jupagose]

Hi, tks to take care about this and tks for this great project.

1. If you are an intesive user, think on 40.. 50 connections by day, it means you must have 1500 port opened by month 18000 by year. To open simultaneous sessions we can save not one but a list of used ports, usually a support user have between 1 and 4 simultaneous sessions.
2. Each port saved must be tested if the port cannot be used we must increment it until one is available as currently done, and must be replaced on config. On the same device it is strange that ports are reserved unless new applications are installed.
3. You are ok, (sorry I'm a windows user ) This can be achieved using the .json config file to store the list of used ports.
4. If you check teamviewer/Anydesk at firewall, there is only a few ports opened by them.

Let me know what you think about it.

Thank you again for the time invested in this great project.