metadata: Print a user-friendly error message if jinja template rendering fails.
metadata: Print a user-friendly error message if jinja template rendering fails.

dan-blanchard/conda-build,sandhujasmine/conda-build,rmcgibbo/conda-build,dan-blanchard/conda-build,ilastik/conda-build,mwcraig/conda-build,ilastik/conda-build,ilastik/conda-build,mwcraig/conda-build,sandhujasmine/conda-build,mwcraig/conda-build,sandhujasmine/conda-build,dan-blanchard/conda-build,rmcgibbo/conda-build,rmcgibbo/conda-build