store: unindent most of the contents of the for loop in _auxencode() by refactoring for i, n in enumerate(res): if n: <main code block> to for i, n in enumerate(res): if not n: continue <main code block> (no functional change)

store: optimize _auxencode() by assigning to the list elements of the path

store: optimze _auxencode() a bit by grouping the reserved names by length This reduces perffncacheencode wall time on Windows 7 x64 for my netbeans clone here from 4.3 to 4.0 (7% faster).