add set_range_style by a simple way

[Harpsichord1207]

[kevmo314]

Thank you for your contribution! For a little more context, what's the motivation for this method instead of requiring the user to explicitly iterate over the range?

[coveralls]

Coverage decreased (-1.7%) to 91.615% when pulling 731ed890bd22f12231aca282852c7b56272d7d57 on Harpsichord1207:dev into 70dd88a3a6653ecc74c4122daa32dcd6a84d2de1 on kz26:dev.

[Harpsichord1207]

Thank you for your contribution! For a little more context, what's the motivation for this method instead of requiring the user to explicitly iterate over the range?

Hello, sorry to reply late, in my case, I need to merge some cells, but when i merged them, there 's something wrong with boders, and i found a same issue #74, so i try to write a function to fix it.