Use tokstyle in the cmake travis build.

[iphydf]

This checks that (some of) the code follows some simplicity and naming
guidelines set by the tool.

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This change is 

[hugbubby]

Reviewable status: 0 of 1 LGTMs obtained

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.travis/cmake-linux, line 12 at r1 (raw file):

travis_install() {
  curl -L https://github.com/TokTok/hs-tools/releases/download/v0.2/hs-tools-v0.2.tar.gz | tar xz -C $HOME

Instead of doing this, we can do the following:

1. Use the github api to automatically get the latest release for the tokstyle tool, so we don't have to update this file every release.
   Solution here: https://stackoverflow.com/questions/24085978/github-url-for-latest-release-of-the-download-file

2. Create releases for the tokstyle tool and automatically download that package (and whatever hs-tools we believe we need in the future) rather than gather them up in this hs-tools repo and download that.
   We're not an operating system - we will solve more problems by doing rolling release than by wasting time gathering them up into a single hs-tools repo package and testing that beforehand.

[iphydf]

Reviewable status: 0 of 1 LGTMs obtained

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.travis/cmake-linux, line 12 at r1 (raw file):

Previously, hugbubby wrote…

Instead of doing this, we can do the following:

1. Use the github api to automatically get the latest release for the tokstyle tool.
   Solution here: https://stackoverflow.com/questions/24085978/github-url-for-latest-release-of-the-download-file

2. Create releases for the tokstyle tool and automatically download that package rather than gather them up in this hs-tools repo and download that.
   We're not an operating system - we will solve more problems by doing rolling release than by wasting time gathering them up into a single hs-tools repo package and testing that beforehand.

I like this idea. I'd still like to do this for now, and then change this repo together with all the haskell repos so they behave the same. The hs-tools repo will stay, because we want to build some tools that aren't developed by us there.

I'll make a PR into tokstyle to make releases, but I don't want that to block the adoption of tokstyle into the c-toxcore build, since without it, I have to manually run it on every PR.

[iphydf]

Reviewable status: 0 of 1 LGTMs obtained

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.travis/cmake-linux, line 12 at r1 (raw file):

Previously, iphydf wrote…

I like this idea. I'd still like to do this for now, and then change this repo together with all the haskell repos so they behave the same. The hs-tools repo will stay, because we want to build some tools that aren't developed by us there.

I'll make a PR into tokstyle to make releases, but I don't want that to block the adoption of tokstyle into the c-toxcore build, since without it, I have to manually run it on every PR.

Done.

[hugbubby]

Reviewed 1 of 1 files at r2.
Reviewable status: complete! 1 of 1 approvals obtained