single trailing param starting with ':' should prepend ':'

related bug in irc-message ->
https://github.com/expr/irc-message/pull/12

	modified:   lib/POE/Filter/IRCv3.pm
add escapes vs no-escapes bench

	new file:   bench/put_escapes.pl
travis; drop 5.19

	modified:   .travis.yml
v1.001001

  - Single trailing param starting with ':' should prepend a ':'
    Related bug in JS 'irc-message' (derived from this dist):
    https://github.com/expr/irc-message/pull/12

  - Minor optimizations

  - Happy CPAN Day!