[encoding] Use encoding dialog for the first pass (no re-use yet)

[eumagga0x2a]

This patch falls way short of the goal to use the single instance of the encoding dialog for both the first and the second pass. It just replaces the working dialog with the encoding one for the first pass with related additional tweaks like disabling the "Advanced" tab and making information about remaining time available. The benefit: it is now possible to minimize Avidemux to the notification area during the first pass too (see reference). Without re-use of the dialog instance, the application window will pop up after the first pass though.

The patch makes also the "Pass 1" translatable and hides the disfunctional shutdown checkbox and priority combo – on Linux and Mac completely, on Windows only for the first pass. The name of the priority label is changed to clarify its purpose when used in code elsewhere.

Automatic shutdown after encoding can't work now, of course, as the value of shutdownRequired is not evaluated in the destructor and ADM_shutdown is never called. IMVHO, this functionality should be either fixed or the checkbox removed / hidden to avoid user confusion.

[eumagga0x2a]

I'm sorry, please delay the review / don't merge now even if it were acceptable. I'm rather close to implementing encoding dialog reuse, it would make more sense to handle a complete solution.

Thanks!

[mean00]

No problem, it was still on the todo