Merge pull request #1 from altiscope/yamaszone/installation_macos_linux

Installation step for macOS/Linux

Author: yamaszone

README.md

@@ -1,2 +1,21 @@
 # `stack` CLI
 Airbus UTM Platform `stack` CLI
+
+## Installation
+
+### macOS/Linux one-liner 
+```
+curl -sSL https://github.com/altiscope/platform-stack-cli/releases/download/v1.10.0/stack_$(
+    bash -c '[[ $OSTYPE == darwin* ]] && echo darwin || echo linux'
+  )_amd64 -o stack && chmod a+x stack && sudo mv stack /usr/local/bin/
+```
+
+### macOS
+```
+curl -sSL https://github.com/altiscope/platform-stack-cli/releases/download/v1.10.0/stack_darwin_amd64 -o stack && chmod a+x stack && sudo mv stack /usr/local/bin/
+```
+
+### Linux
+```
+curl -sSL https://github.com/altiscope/platform-stack-cli/releases/download/v1.10.0/stack_linux_amd64 -o stack && chmod a+x stack && sudo mv stack /usr/local/bin/
+```