MIME: changed type for bmp to image/bmp. At least Chrome, Safari, and Edge do no show image/x-ms-bmp when requested directly (and instead show a download dialog), but do so for IANA-registered MIME type image/bmp. Mozilla considers doing the same (https://bugzilla.mozilla.org/show_bug.cgi?id=1422725). Further, Apache uses image/bmp since the bmp extension was added to mime.types in Apache 1.3.6 (and also used it at least since 1.3.0 in magic-based type detection). The bmp extensions with the image/x-ms-bmp type was added in 863:57cb2052dcc6 (nginx 0.4.14), as a part of a large mime.types change, and it is not clear why image/x-ms-bmp was used instead of image/bmp. As such, changed MIME type for bmp files to image/bmp. Requested by Yuriy Izorkin.