This is a higher level, more concise wrapper for bitsets which supports
efficiently counting and iterating over set bits. It's similar to
std::bitset, but the latter does not support efficient iteration (and at
least in libc++, the count algorithm is subpar, not that it really
matters). The converted uses include both bitsets and, notably,
considerably less efficient regular arrays (for in/out registers in
PPCAnalyst).
Unfortunately, this may slightly pessimize unoptimized builds.