added icons: go-next, object-rotate-left, process-stop, zoom-in, zoom-out

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branch : develop
Merged in grumpi/valentina-grumpifork2/develop (pull request #7)

added icons: go-next, object-rotate-left, process-stop, zoom-in, zoom-out

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branch : develop
Copying translations did not work on Windows system.

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branch : develop
Set icon theme before showing windows.

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branch : develop