Auto install scripts fail for windows and linux

The scripts on the following page do not work 100%. 
(https://docs.radixdlt.com/docs/getting-rust-scrypto)

**Windows script fails with:** 

   ```
Compiling cc v1.2.10
error: linker `link.exe` not found
  |
  = note: program not found
```

**Linux script fails with:**
`sh: 108: source: not found`

Both cases are freshly installed VMs.