Did Nathaniel Hawthorne mean for The Scarlet Letter to be a feminist novel?

Arguably, the answer is yes. There is plenty of evidence to suggest that this was done purposely, and there is also supporting history showing that Hawthorne was, in fact, a huge supporter of specific women in history, Anne Hutchinson (whom he mentions in the novel), being definitely one of them. 

While the novel can be considered "proto" feminist (published before the actual feminist movement of the late 1960s itself), it definitely has more than enough ways to show Hester as a progressive and independent woman of her time. 

First, Hester can exist as a character of her own. If she were not a character, she would be a completely independent and self-sufficient woman; this is something that was simply not seen in the 17th century, when the novel is set. 

Second, Hester defies the system and strongly defends her pregnancy, her right to keep the name of the out-of-wedlock father secret, and her right to keep her daughter, even in front of the magistrate. She stands up for herself in the face of the Reverend Mr. Wilson, Chillingworth, Dimmesdale, the villagers, and (sometimes) even Pearl. She makes dealings with sailors, tends the deathbed of Governor Winthrop, and goes in and out of her dwelling as she sees fit. She is the master of her days and nights. That is much more than any woman of her time would have done for herself. 

Hester carries out the punishment of the scarlet letter, and gets out of prison to live life as a single mother, and as a pariah of the village. This, she does shamelessly and in complete awareness of what is coming her way. Still, rather than engaging in the futility of expecting Dimmesdale to acknowledge her, or Pearl, she moves on with her life the best way that she knows how. 

Hester also changes, as a person and as a woman. Her scarlet letter had left her "able", and turned her into a heroine of the people. She is also stronger, less passionate, more immersed into thought; she is a full person whose punishing, scarlet letter

....was the symbol of her calling.

Therefore, Hawthorne gifts the reader with a female main character who is, in laymen terms, "no-nonsense". Rather than presenting an ornamental female playing the role of damsel in distress, he gives us someone comparable to "the sainted Anne Hutchinson", who also removes herself from mainstream society to fulfill what she believed was her mission in life.