Like Raghu says, this clearly sounds like a case of mistaken copy/paste. However, I have a few other things for you to contemplate.
1) Since you are in a PhD program then you need to realize that you've entered into a fairly small professional world. The only appropriate way to respond to interpersonal problems such as this is to talk it over with the person(s) involved. Jumping straight to legal action or public shaming is a sure-fire way to destroy your professional reputation end your career before it starts. In general, pursing "pay-back" is never an appropriate response in a professional setting.
Even if your actions don't spread beyond your graduate department, these are the people who are going to vouch for you in front of the larger community when it comes time to assemble a dissertation committee and ask for future letters of recommendation. Destroying these relationships is what is known as "burning bridges"
2) This is tangentially related, but maybe you need to hear it. (Advice is free, amirite?) Anyone pursuing a PhD needs to learn early how to deal with criticism, because you will be given a lot of criticism. Committees are going to criticize your portfolio and thesis. Reviewers are going to criticize your papers. Partners and co-workers are going to disagree with you in public and in meetings.
It appears as though you've taken an honest mistake and then turned it into a personal insult. Then you've decided you need to retaliate based on that perceived slight, all without talking to the person involved. You should take a moment to reflect on your personal disposition and whether you're really OK with being criticized for the rest of your career. Of course, criticism does not mean subjecting yourself to personal insults.
However, if this person really intended to hurt you, the only professional response is to grin and bear it while bringing it up with the relevant supervisory bodies.
3) Which brings me to the next point, which is that most graduate programs have a designated person (or committee) who exists to mediate conflicts between graduate students and their advisers or other authority figures in the department. (For example, in my graduate department this person was just the director of graduate admission.)
If you really feel as though there is a personal conflict here, the first step (as always) is to discuss it with the person involved. If you feel you cannot talk to this person yourself, the alternative is to go to this trusted mediator and ask them to inquire about the situation for you. Then, if it turns out that there is a personal conflict that you cannot resolve yourself, the next step is to turn to this mediator or other supervisory individual and seek redress there.
4) Lastly, you need to realize that nobody has guaranteed you the right to be liked by everyone you work with. This does not mean you need to subject yourself to their snide comments or insults (they are expected to be professional as are you). However, if a genuine conflict exists and it is unresolvable then there is not a lot you can do other than to agree to disagree and move on with your life. This is true whether the conflict is between you and a co-worker, supervisor, or subordinate.
Again, in no case is it professionally appropriate to seek "pay-back".