Optionally add `azcopy` to the `azure-cli` feature

[aelij]

azcopy is a very useful tool for copying large amounts of data to/from Azure Storage.

How to install:

curl -Lo azcopy.tar.gz https://aka.ms/downloadazcopy-v10-linux && \
    tar -xf azcopy.tar.gz && \
    mv azcopy_linux_amd64_*/azcopy /usr/local/bin/azcopy && \
    rm -rf azcopy_linux_amd64_* && \
    chmod +x /usr/local/bin/azcopy

[eljog]

Hi there, Thank you for sharing your suggestion. Since the az cli and azcopy are independent tools that are versioned, maintained and installed independently azcopy might not fit well within the azure-cli feature. But it would definitely worth contributing an new feature for azcopy