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Closes #5

See merge request !1

To use OpenMP, force `OTB_USE_OPENMP`

Otherwise clang complains about `PixelTraits<VLV>` being unable to fetch
`VLV::Length`.

Indeed, there is no need to test the value of the last pixel against zero if
it's to return zero in case the pixel equals zero...

We cannot directly use `GetParameterStringList()` as the objective was to avoid
`VectorImage`s. Hence the explicit use of image readers.

TODO: make this application pipelinable

Relates to s1tiling#8

This'll need to be moved elsewhere

- when module/lmod is detected
- and fill it with otb module when any is found