New Feature Request: PlayBack and add events

[Borgonovo-Santos]

• Open a CSV file
• Select the frequency (like baud rate selection, insert the frequency for the playback)
• Press play.
• The space bar works as Play/Pause on this playback mode.
• Sample position selection (fine selection) - box for up (forwards) and down (backwards) or manual introduction.
• Add labelled events to the raw data (synchronized with the actual sample data).
• Save new CSV files with events included.

Other preview features working as they normally do. (such as plot area, size, variables selection...)