[dwm] spelling

hi

just a minor correction on the website: http://wmii.de/dwm/
english is not my native language, but i believe "dwm don't
distinguishes" should be "doesn't distinguish":

58c58
< dwm don't distinguishes between layers, there is no floating or

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>                       dwm does not distinguish between layers, there is no floating or
keep up the good work on this awesome wm!
ILF