Write an osc file for excluded address so that they can be easily opened in JOSM or elsewhere.
Make it clear whether the new addresses are before or after validation, and add option for getting the other.
Change the operator == to prevent creating a copy of the object, and get a list of values outside of a for-loop to save some time there.
Move check for nearby addresses into its own method, and divide the grid into 4 sections to reduce the number of comparisons made.
Add zip code file and building file fields
Start working on reading zip codes. Reading relations is not fully supported yet.
Add code to read in buildings; relations are not supported yet.
Correct method calls at end of methods.
Add skip attribute when reading in ways to make sure they are actually buildings.

For the moment, use YearBuilt, but not all buildings have the YearBuilt attribute, and something else needs to be used.