conda-build warnings

[xhochy]

Building the feedstock currently issues the following warnings:

Adding .* to spec 'arrow-cpp 0.12.0' to ensure satisfiability.  Please consider putting {{ var_name }}.* or some relational operator (>/</>=/<=) on this spec in meta.yaml, or if req is also a build req, using {{ pin_compatible() }} jinja2 function instead.  See https://conda.io/docs/user-guide/tasks/build-packages/variants.html#pinning-at-the-variant-level
WARNING:conda_build.utils:Adding .* to spec 'arrow-cpp 0.12.0' to ensure satisfiability.  Please consider putting {{ var_name }}.* or some relational operator (>/</>=/<=) on this spec in meta.yaml, or if req is also a build req, using {{ pin_compatible() }} jinja2 function instead.  See https://conda.io/docs/user-guide/tasks/build-packages/variants.html#pinning-at-the-variant-level
Adding .* to spec 'parquet-cpp 1.5.1' to ensure satisfiability.  Please consider putting {{ var_name }}.* or some relational operator (>/</>=/<=) on this spec in meta.yaml, or if req is also a build req, using {{ pin_compatible() }} jinja2 function instead.  See https://conda.io/docs/user-guide/tasks/build-packages/variants.html#pinning-at-the-variant-level
WARNING:conda_build.utils:Adding .* to spec 'parquet-cpp 1.5.1' to ensure satisfiability.  Please consider putting {{ var_name }}.* or some relational operator (>/</>=/<=) on this spec in meta.yaml, or if req is also a build req, using {{ pin_compatible() }} jinja2 function instead.  See https://conda.io/docs/user-guide/tasks/build-packages/variants.html#pinning-at-the-variant-level

I will release 0.12.0 once it passes and fix them in a follow-up PR.