type.js calls drivers "mime types"

[jankeromnes]

@espadrine in type.js:

• nameFromType is advertised as being an "Array of mime types (Strings)".
• addType inserts "mime types" into this array.
• Actually, only three "mime types" are added, "dir", "binary", and "text".

Those are not mime types. We should change the occurrences of "mime type" in type.js to "type", and fs.js:138 should not set file.meta.type to type.nameFromType[file.type]. Mime types should instead be looked up properly.

This confusion causes all new mime types to be wrongly set to "binary" or "text" (however, in our logic "dir" is a valid mime type for folders, should we change that?), these problems surface in #188.

[jankeromnes]

Well, now that we're accepting driver types and mime types as just "types" this is not an issue anymore...