Login cleanup IE8 fixes

@jancborchardt seems my commits to login-cleanup got overwritten when you merged master. I assume you force pushed the branch. This PR fixes the IE8 css issues again. Dunno why the `white-space: nowrap;` was missing as https://github.com/owncloud/core/pull/4184 is already merged.

@DeepDiver1975 can I have quick IE8 review by looking at the login screen? before / after screenshots are in https://github.com/owncloud/core/pull/4173#issuecomment-21487159

@karlitschek @MTRichards a +1 if you want this in :)