Make TIFF compression level configurable
The TIFF compression level is currently hardcoded to 9 (Z_BEST_COMPRESSION), which doesn't lead to a noticeably smaller output file, but heavily increases the number of required CPU cycles. Make the level configurable and default to level 5.
This is equivalent to the solved issue regarding the PNG imageio module (#11695), with the exception that TIFF supports more than one compression scheme (including "uncompressed") and darktable already has a combo box to choose several schemes. The attached patch is a direct port of the commit (860def4eab3b1fc5b838d27bcc2f43ab81e2f295) which implemented the same feature for PNG.
The patch uses the UI string "compression" for the compression scheme and "compression level" for the compression level. This is a bit problematic because "compression level" is not yet localised in any language. Also the EXR module already uses "compression mode" and the WebP module already uses "compression type", this could be consolidated into a single string which works for EXR, WebP and the TIFF compression scheme.