Remove check for '\r\n' when processing pub args

[wallyqs]

The parser has already dropped CRLF by when processPub is called, so we can skip doing these checks there. This change also refactors the pub arg tests to use t.Run closure along with more checks for when parsing reply inboxes.

• Link to issue, e.g. Resolves #NNN
• Documentation added (if applicable)
• Tests added
• Branch rebased on top of current master (git pull --rebase origin master)
• Changes squashed to a single commit (described here)
• Build is green in Travis CI
• You have certified that the contribution is your original work and that you license the work to the project under the MIT license

/cc @nats-io/core

[coveralls]

Coverage decreased (-0.06%) to 91.938% when pulling 5e58e07 on wallyqs:process-pub-args-crlf into c3e0951 on nats-io:master.

[coveralls]

Coverage decreased (-0.1%) to 91.875% when pulling c8f151e on wallyqs:process-pub-args-crlf into c3e0951 on nats-io:master.

[petemiron]

LGTM.