Artfully toggling between the ephemeral memories associated with the infamous Chelsea Hotel, and the more granular concerns of its present residents, Maya Duverdier and Amélie van Elmbt’s new documentary, the Martin Scorsese executive produced “Dreaming Walls: Inside the Chelsea Hotel,” is a concise reflection of the erasure of historical monuments in the name of gentrification. Centralizing the protracted construction process that closed down the hotel in 2011, but allowed its long-term residents to stay, the doc mainly follows the hold-outs in their ninth year of construction, many who view the hotel as one the last examples of bohemian, and affordable, living in Manhattan.