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* Fix fileobj I/O undeterministic behavior

Ever since the file-like object support was added in #1158, the test
was occasionally failing in CI. This PR fixes this.

* Switch to cmake for build
* Hide symbols

Currently `libsox` on Linux is compiled with GPU OpenMP and it interferes with the version PyTorch uses (Intel in case of binary distribution). This PR disables OpenMP support for `libsox`, while we investigate the way to use the same OpenMP as PyTorch's version.

* Use cmake for third party

* Apply patch to libmad

* Update gitignore

* Update docker test image