Disabled html select formatting is consistent among the themes

[spyhunter99]

I ran into a few minor issues with html select boxes not having consistent visualization across themes when adding or removing the disabled attributed. Here's some examples

Example for darkly

Solar, note that non disabled are an off white color, and disabled is the default white

Vapor, note that non disabled are dark purple color, and disabled is the default white

Quartz, in this case both the password box and the select have the disabled flag, select is a white background with disabled and without disabled is a transparent setup

Might also be a good idea to edit the bootswatch demo pages to have examples of disabled inputs for all types to verify consistency

[thomaspark]

@spyhunter99, thanks for the suggestion. Fix incoming.