Update submodules: parser (new commits)

parser:
    31d3ebc Greg Holmes <greg@dmdirc.com>
            Tidy up SRVRecord.

            Adds an AutoCloseable version of InitialDirContext.
            Fixes-Issue: CLIENT-521

            Gerrit: http://gerrit.dmdirc.com/3950

Change-Id: I97f42f42c76da2adefaa5f8828c608be7f343dd6