Cannot install on osx readline can't find files

[symgryph]

According to the 'readline' package it hasn't been maintained since 2012. We should be using gnureadline according to the readline source code installs. Installing readline fails with:

clang: error: no such file or directory: 'readline/libreadline.a'
    clang: error: no such file or directory: 'readline/libhistory.a'
    error: command 'clang' failed with exit status 1

    ----------------------------------------
Command "/usr/local/opt/python/bin/python2.7 -u -c "import setuptools, tokenize;__file__='/private/var/folders/5g/pn57rcp935zfpmlhkqy9nmd80000gn/T/pip-build-EByhcv/readline/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /var/folders/5g/pn57rcp935zfpmlhkqy9nmd80000gn/T/pip-SXBtVu-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /private/var/folders/5g/pn57rcp935zfpmlhkqy9nmd80000gn/T/pip-build-EByhcv/readline/

[ghost]

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