Prevent user from patching current session into negative time

[Mason-Flannery]

Currently, there are no safeguards to prevent negative patching (a new session can immediately have a -30 offset if the user immediately patches in time)

[Mason-Flannery]

If this occurs, timestamps get very large

[Mason-Flannery]

If this occurs, timestamps get very large

I should add that the tracking still happens correctly, but a negative parse to an unsigned value for display purposes causes visual problems