.travis.runonce.bash: care about exit status

Squashed commit of the following:

commit aa8823331ebccebdca83810545b167deb2e6303e
Author: Mikaela Suomalainen <mikaela.suomalainen@outlook.com>
Date:   Tue Jul 15 20:47:29 2014 +0300

    .travis.yml: remove duplicate x

commit ef3b363aa6b692c771733f1b4a9d352c9224f3d0
Author: Mikaela Suomalainen <mikaela.suomalainen@outlook.com>
Date:   Sun Jul 13 22:32:10 2014 +0300

    .travis.runonce.bash: add spaces

commit 004905729f954b5368510098fa2cac2a7181964a
Author: Mikaela Suomalainen <mikaela.suomalainen@outlook.com>
Date:   Sun Jul 13 22:28:48 2014 +0300

    .travis.runonce.bash: pipe msgcheck to true

commit d5bdeac5f7754c9443c983f374d41a2f9bc0d1b3
Author: Mikaela Suomalainen <mikaela.suomalainen@outlook.com>
Date:   Sun Jul 13 11:04:40 2014 +0300

    .travis.runonce.bash: remove RTFD

    There is now hook for it at GitHub.

commit e1dab24f0f6f1c406b2284298a2e8ab3908bdc23
Author: Mikaela Suomalainen <mikaela.suomalainen@outlook.com>
Date:   Sat Jul 12 23:34:14 2014 +0300

    .travis.runonce.bash: care about exit status

    This excludes msgcheck, because it's over-sensitive and always returns
    exit value which logic I don't remember unless everything is correct
    according to it.

    Oh and the behaviour before this commit allows everything to fail
    without having exit code which shows that it failed and we wouldn't
    notice any failures in near future.