Font: remove dependancy on sstream

no sense in adding overhead for such small gain in code readability
Font: fix debug mode

neglected to update the debug code when lineW was taken out
Font::SizeString: fix some problems with \n

1. if a \n is encountered, then everything preceeding it goes on the line
2. we shouldnt increment numChars for a line break caused by wrapping
3. implementing a less costly method of handling strings of all whitespace

this should fix a minor regression from b4ca537
use L'\n' instead of L"\n" when searching for a newline

im supposing it is more efficient
Font: fix exception when right/centered text doesnt fit nicely