Title Case with Small Words

Implement title_case(text) following a common style guide:

• capitalise the first letter of each word and lower-case the rest
• keep these small words lower case: a, an, and, as, at, but, by, for, in, of, on, or, the, to unless they are the first or last word
• words separated by hyphens are capitalised on each part (state-of-the-art → State-of-the-Art, with the small-word rule applying to inner parts)
• collapse runs of whitespace into single spaces