Better behavior when left-clicking a TCO

[Sawuare]

Instead of calling MouseMoveEvent(), the TCO's "text float" text and position are updated.
This prevents left-clicking the right edge of a resizable TCO from decreasing its size.

Also, removed an unused variable: m_oldTime

[zonkmachine]

This prevents left-clicking the right of a TCO from decreasing its size.

Yeah, I don't think I've seen this reported before but I can confirm the issue. You basically end up nudging the TCO a bit to the left sometimes when grabbing the edge. Fix confirmed.
It's not really an enhancement but a ux/bug and I think it's correct to address this in 1.2 .

[musikBear]

I feel that it can be a tad difficult to 'grab' the move-handle on notes <= 1/16. I quite often resize the note instead. Its very simple to 'fix'. Setting magnification to 200% let me grab notes easy -Will this fix influence 'grabbing' of <= 1/16 notes?

[zonkmachine]

I feel that it can be a tad difficult to 'grab' the move-handle on notes <= 1/16

OT. This PR is about TCO's in the Song Editor and not about grabbing notes.

[musikBear]

OT. This PR is about TCO's in the Song Editor and not about grabbing notes.

ooops.. but Note-TCO cant change size(?) so AUT and B&B..
I will write a ticket for the note-grab