Allow arbitrary extensions for disk images when format is specified

[sdsnatcher73]

Don't know whether this can be done easily but it would make life a bit easier on me (and possibly others). Many disk based software use multiple disks. Because I have my MSX images named in 8.3 format (because I use them on MSX as well) I use the following convention for multi disk sets:

NAME.FD1
NAME.FD2
...
NAME.FDA (disk 10)
etc.

If I want to write such a (raw sector dump image) to disk with:
gw write NAME.FD1 --format msx.2dd
I get the error message:
Known suffixes: .a2r, .adf, .ads, .adm, .adl, .d81, .d88, .dcp, .dim, .dsd, .dsk, .fdi, .hdm, .hfe, .ima, .img, .imd, .ipf, .mgt, .msa, .raw, .sf7, .scp, .ssd, .st, .xdf

What would be great is that if --format is specified and the suffix is not known the IMG suffixes values could be applied.

[keirf]

I'm not sure I like this by default. I could add an --image-type option or something. But ultimately, if you have to mess with the command line, is it much better than renaming or copying the image file to have the required extension? It's easy enough to add but pointless if noone would actually be bothered to use it.

[sdsnatcher73]

I get your point about making it default behaviour. The option --image-type would prevent me to having to rename the image and renaming it back afterwards. Another option could be to have a .gwconfig file in the user's home directory where they could map suffixes to formats, e.g.

[image-types]
*.fd?=img