getAuthorName returns firstname + NULL when last name is null

[gengweifeng]

hi, when i get the issue's authorName, the return is strange. the api version is 3.0.0, and the return is "authorName null". when i use the api version 2.6.0, i found that the author's lastname is null and the firstName is truly full name. so the full name it return is "authorName null"

[alexeyOnGitHub]

I recall this was added as a workaround for Redmine REST API limitations when they clumped first and last name together in one field and we did some parsing to guess what was first and last there.

        if (author != null) {
            result.setAuthorId(author.getId());
            result.setAuthorName(author.getFullName());
        }

    public String getFullName() {
        return getFirstName() + " " + getLastName();
    }

I guess getFullName() can use an empty string if getLastName() returns NULL.

[alexeyOnGitHub]

fixed