FreeRDP version 2.2.0

See https://pub.freerdp.com/releases/ for the release tarball.

• SECURITY: CVE-2020-15103 - Integer overflow due to missing input sanitation in rdpegfx channel
• #6263 Sound & mic - filter GSM codec for microphone redirection
• #6335: windows client title length
• #6370 - "Alternate Secondary Drawing Order UNKNOWN"
• #6298 - remoteapp with dialog is disconnecting when it loses focus
• #6299 - v2.1.2: Can't connect to Windows7

Noteworty changes:

• fix: memory leak in nsc
• urbdrc
  • some fixes and improvements
• build
  • use cmake to detect getlogin_r
  • improve asan checks/detection
• server/proxy
  • new: support for heartbeats
  • new: support for rail handshake ex flags
  • fix: possible race condition with redirects