Attached patch adds support for multiple FIXes with the same name.
Applies to both branches.
New functionality is in query_and_offset, which now returns the FIX
closest to the passed in location.
Updated route manager to take advantage of this.
Otherwise, query functions return an unspecified member from the set
of identically named FIXes. (This was previously the one occurring
last in the database file, but I don't think anybody counted on that.)