logger: Don't store verbose-magic in the log files.

In r399267, the verbose2magic stuff was edited. This time it results
in magic characters in the log files for multiline messages.

In trunk (and 13) this was fixed by the "stripping" of those
characters from multiline messages (in r414798).

This fix is altered to actually strip the characters and not replace
them with blanks.

Review: https://reviewboard.asterisk.org/r/3901/
Review: https://reviewboard.asterisk.org/r/3902/
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Merged revisions 420897 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 420898 from http://svn.asterisk.org/svn/asterisk/branches/12
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Merged revisions 420899 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: http://svn.asterisk.org/svn/asterisk/trunk@420900 f38db490-d61c-443f-a65b-d21fe96a405b