Monal 6.4.14 (Build 1053, PR #1459)

• Don't crash on unexpected call states
• Don't fail when sending files using the sharesheet
• Implement strict ordering of SCRAM attributes
• Warn if MUC changes from private group to public channel
• Added Chinese appstore description
• Fixed multiple crashes
• Ignore transient MUC errors from prosody
• Fix automatic speaker activation in video calls
• Allow SASL2 without channel-binding and SSDP
• Changed some webrtc values, does this fix the video call problem?