Reword unclear docstrings

[ashwinvis]

• clever enough

docs/simsonsuite.rst
19:readdns() is clever enough to figure out the rest.
32:readplane() is clever enough to figure out the rest.

docs/neksuite.rst
19:readnek() is clever enough to figure out the rest.
48:readrea() is clever enough to figure out the rest.

[ashwinvis]

@jcanton Let me know if you can do this. You were the original author, afterall 😄