Improve speed using stringi package

[GegznaV]

I think this pull request is worth attention awalker89/openxlsx#440: extra speed gives more value.

[ycphs]

Currently the checks fail. Maybe you could check the saveWorkbook method.

[ycphs]

@noamross, it would be great if you could apply the changes here as well.

[noamross]

Hi @ycphs. I'm happy to do this though it will take me a bit to get to it. First I wanted to confirm that you've contacted the original maintainer and CRAN about taking over maintenance - I just want to make sure we aren't fragmenting code ecosystem!

[ycphs]

Hi,

I tried to contact him with via mail and linkedin. Do you have another possibility to contact the original maintainer? I just thought that it is a pity that the package has the status orphaned on CRAN.

[noamross]

I don't have any better contact for them. I agree - I would suggest making a small update fixing the current CRAN notes and submitting to take over the maintenance before doing major updates.

[ycphs]

Published on CRAN

Looking for new enhancements and features.