time control: Support other timestamp formats

[ghost]

Currently the Time Control view only shows (and reads) timestamps in the "s.n" format. There should be a configuration option somewhere to allow displaying the timestamps in various formats, like:

• YYYY-MM-DD hh:mm:ss.nnnnnnnnn
• hh:mm:ss.nnnnnnnnn
• ~ss.nnnnnnnnn~ (done)
• n

Additionally, the text fields should be able to receive and parse any of these formats, no matter what output option is defined.

[ghost]

After a bit more discussion, it was decided that receiving (as in, getting pasted in) a timestamp should only accept the currently configured time format. This is to avoid confusion between formats that we have no way to differentiate programmatically, for example a hh:mm:ss.n format in GMT vs. local time.