Expose remaining options

[arnetheduck]

#51 introduced a pattern for exposing most options available in rocksdb but omitted several types such as WriteOptions etc - the remaining options fall into three categories:

• trivial options like the ones exposed that were missed
• trivial options that nevertheless don't work with the simple template due to naming issues (some are missing setter, or have different naming etc) - these should probably be reported/patched upstream
• complex options that can't be represented well with getters/setters like that

For full flexibility we should have all options mapped - they currently are more or less in the same order as options.h in rocksdb proper so it should be fairly straightforward to complete.