BUG: foamConfigurePaths -foamInstall fails (related to issue #280)

- relied on 'export' keyword, which was removed in commit b8448671

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ENH: foamConfigurePaths support for additional items:

    -label 32|64            specify label size
    -system name            specify 'system' compiler to be used
    -thirdParty name        specify 'ThirdParty' compiler to be used

    -boost ver              specify boost_version
    -boostArchPath dir      specify BOOST_ARCH_PATH
    -cgal ver               specify cgal_version
    -cgalArchPath dir       specify CGAL_ARCH_PATH
    -clang ver              specify clang_version for ThirdParty Clang
    -cmake ver              specify cmake_version
    -fftw ver               specify fffw_version
    -fftwArchPath dir       specify FFTW_ARCH_PATH
    -metis ver              specify METIS_VERSION
    -metisArchPath dir      specify METIS_ARCH_PATH