Change Color Mode, Color Profile, add an option to silence error messages with app.open()

Trying my hand at writing a few batch scripts for a project and have a couple suggestions

Change Color Mode
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Was writing a script for an operation that I do pretty frequently, swapping palettes for a color reduced one, the operation is:

Change the color mode of the sprite to rgb
Load the reduced color palette
Change the color mode of the sprite back to index

The closest thing to changing the color mode, is opening the "color mode changing dialog" through app.command.ChangePixelFormat. It'd be nice to have a quiet method that doesn't open up a color mode changing dialog, but applies your settings directly to the sprite.

App.open with a setting to ignore error dialogs
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I work with photoshop, and sometimes saving the files as png results in the following error when opening up the png file: libpng: iccp: known incorrect srgb profile.

Which is due to the color profile being set to Photoshop ICC profile.

Choosing to ignore the error message would help stop the problem of script pausing for batch operations.

Change Color Profile
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Which brings me to being able to change the color profile directly without having to go through sprite properties dialog. (changing the color profile to 'none' allows the faulty "photoshop ICC profile" png to actually save)