Integrate Bootstrap

[Changaco]

This PR is to unblock #183, it allows customizing Bootstrap by modifying the new style/variables.scss file. Ping @MartinDelille and @Calinou.

[Changaco]

TODO:

• fix the tests
• update the CSS section of the README

[Changaco]

Coincidentally, Bootstrap 3.3.7 has just been released, so we should upgrade before merging this.

[MartinDelille]

This is awesome and will help us make it look nice :-)

Just a question: why not using git submodule to link bootstrap code?

[Changaco]

Just a question: why not using git submodule to link bootstrap code?

It didn't come to mind because I never use them and they have a bad reputation, but I guess we could try.

[MartinDelille]

It is not a big deal when you use it for external projects. A lot of bug have been fixed also. After that I think bower.io is also a simple solution for referencing external code (simpler to use than git submodule). Any preference?

[Changaco]

No Bower. Preferred solutions:

1. git submodule if it's not a pain in the ass
2. a tarball stored with git-lfs and unpacked at the appropriate time
3. just leave things as they are now

[MartinDelille]

Let's go with 3, but using submodule afterward will make handling upgrade easier.

[Changaco]

We can make it easy to upgrade no matter which option we choose.

[MartinDelille]

Maybe, but using submodule reduce the codebase and the diff. Although it is always possible to patch a vendor code by forking it and referencing the fork in the submodule.

[Changaco]

Option 2 (using a tarball and git-lfs) has the same advantages, only option 3 (storing the files directly in our git) generates diff noise.

[MartinDelille]

You're right. I never used git-lfs yet.

[Changaco]

I explored the possibilities of using git-lfs for this, but if we did that then we'd have to add git-lfs as a required dependency (right now it's only used for the PDFs of MangoPay's terms, so it's optional).

[Changaco]

Deploying this broke everything because libsass failed to compile with the obsolete version of gcc present on the server.

[Changaco]

Upstream has a pull request to bring back compatibility with older GCC versions, sass/libsass#1623, but we can't wait for that.

[Changaco]

The libsass python package actually provides binaries. pip wasn't using them because it was also out-of-date. After upgrading pip, installing an up-to-date precompiled version of libsass succeeded, and re-deploying version 126 of liberapay worked.

[MartinDelille]

Regarding the submodule option, usually, I create a vendor directory in the root directory. Do you prefer me to keep the current architecture and I will have to find how to make a submodule that point to a repository subdirectory (https://github.com/twbs/bootstrap-sass/tree/master/assets/stylesheets).

What do you prefer? If you think it is a waste of time, tell me.

[Changaco]

There's no point in changing the integration now, we went with option 3 (directly including the Bootstrap source in our git), let's stick with it until we have a good reason to switch to something else.