csplit: first implementation

[mkindahl]

A first implementation of csplit.

[mkindahl]

Sorry about the time, not able to spend as much time as I intended. There are still things that I think can be improved in the code, but I can take them as separate PRs. Please note that the added tests need to be executed manually: there can be differences that does not indicate an issue.

[mkindahl]

Something seems to be wrong with the job to build using the beta compiler. Looking at the output it looks like it is stalling when retrieving the cache information:

...
creating directory /home/travis/.cargo�[0m
adding /home/travis/build/GrayJack/coreutils/target to cache�[0m
creating directory /home/travis/build/GrayJack/coreutils/target�[0m
adding /home/travis/.rustup to cache�[0m
creating directory /home/travis/.rustup�[0m
adding /home/travis/.cache/sccache to cache�[0m
creating directory /home/travis/.cache/sccache�[0m


No output has been received in the last 10m0s, this potentially indicates a stalled build or something wrong with the build itself.
Check the details on how to adjust your build configuration on: https://docs.travis-ci.com/user/common-build-problems/#build-times-out-because-no-output-was-received

The build has been terminated

I have tried to build it locally with both nightly, stable, and beta, and it works fine.

[GrayJack]

Awesome work, thanks!! Also don't worry about time, I gave me some days to do some other work and I returned today to this project. 😃

Besides these minor things I put here, there was some occurrences of unneeded return statement and one length compared to zero using clippy with pedantic lint allowed, can you "fix" that too?

[GrayJack]

There are still things that I think can be improved in the code, but I can take them as separate PRs

Can you open issues about each one so we can easily keep track of them?

[mkindahl]

There are still things that I think can be improved in the code, but I can take them as separate PRs

Can you open issues about each one so we can easily keep track of them?

Of course. :)

[GrayJack]

Looks like I pushed a something that breaks 1.37 compatibility