add option to disable case sensitivity when searching rooms

[craftyguy]

In my vimrc, I set ic (ignorecase) because I'm lazy and can't be bothered to remember the exact casing used for whatever I'm trying to find. Currently when searching a list of rooms (and probably other stuff too?), the search is case-sensitive. An option to disable this would be really great!

[ulyssa]

Someone also brought up smartcase in #iamb-users today. This would definitely be nice to have, along with maybe a fuzzy search option.

[sempruijs]

Case insensitive should be the default.