Simplify install w/ 1 line command

[djfarrelly]

Purpose

We currently have to curl and chmod and have to keep in mind a long URL for the curl command which has the version embedded. It would be way simpler if we took inspiration from other projects like nvm and used a curl'd bash install script:

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.34.0/install.sh | bash

Idea

We could upload a generic script where the output could be:

curl -o https://scripts.buffertools.com/buffer-static-upload.sh | bash

Or allow people to set the version they want via environment variable

BSU_VERSION=0.4 curl -o https://scripts.buffertools.com/buffer-static-upload.sh | bash

The script would also check if the static upload cli matching that version already is installed which could save time spend downloading.

Notes

We might have to think about whether this script installs it globally in somewhere like /usr/bin/local/buffer-static-upload or locally in that directory.