Remove all trailing 'u' from integer literals
Remove all trailing 'u' from integer literals

rustc now prints a warning for these literals, since it wants you to
specify the size of the integer. For example, '6u32' rather than just
'6u'.

So, I've simply removed the 'u' suffixes. This commit only affects
tests, and so I can't see any reason why these numbers particularly need
to be unsigned.

DanSimon/peruse