Else a lot of time is then spent moving data forth and back with memcpy
on further appends.

Reworked hitK* and associated set flags to liveseparately not to create
holes.

* master:
  A+C: Add information about my contributions

splitX bugfix test + simplification

In the process of going through b code I've noticed that splitX bug fix (commit 5c732b36) handling logic was not covered by tests for edge cases and that this edge-handling logic itself can be simplified. Please find patches which add corresponding test and do the simplification attached.

The simplified logic will be handy for upcoming work.

Please see details in individual commit messages.

Thanks beforehand,
Kirill

As requested by @cznic add information about me and my company to
AUTHORS and CONTRIBUTORS.

Btw, I'm not a lawyer and maybe there are country differences, but I
used to think that:

- author is the person who actually creates the work.
- copyright holder is who owns the copyright on that work (i.e. the
  person, or company he is working for or someone else).

The `AUTHORS` file however gets it the other way - it says to put there
information about who is "copyright holder" which goes counterwise above
classification.

----

I understand however that the exact A+C approach is taken from the Go
project so let's also continue following it here.

We are simplyfing commit 5c732b36 (Fix splitX bug.) here:

By always passing to splitX i of index entry that is actually going to
be used for traversal(*) we don't need to consider edge cases, such as
when to move to next slot, inside splitX itself and this way there is no
need to keep relookup logic there.

So inside splitX it becomes very simple:

	- i <= kx  -> go left
	- i > kx   -> go right

The logic to advance i by 1 on exact key hits was already there in Set
and Put so it is natural for them to pass correct slot index to splitX.

(*) i.e. index of next slot on exact index entry key hit - see previous
    patch for explanation