OCR Customization Page added

A new OCR Page has been added to help with those cases where the text is not being correctly detected by default. So, for example, in cases where there's a lot of menu text, or Japanese text that's not being picked up, you can customize some settings to change how the screenshot is preprocessed before being sent to Google's API. You can: lower the OCR confidence threshold to pick up text, restrict the OCR to a particular region in the image, change the contrast of the image (useful for some smooth fonts), or only use certain colors in the image (very useful for pixel fonts). You can access the new page from the top of the "Settings" page.