'help set' shouldn't break long lines

[jsnajdr]

Fix the code that detects if a help text is preformatted and prevents breaking long lines. The current code doesn't work for !help set (or anything else)

[julianhyde]

Thanks for logging this bug, @jsnajdr. I didn't use your fix, but the missing space made me notice how all the spaces were being stripped when SqlLine.properties was being read. Fixed in dcda196.