added install instruction for powershell users

docs/docs/index.md

@@ -16,9 +16,14 @@ Poetry provides a custom installer that will install `poetry` isolated
 from the rest of your system by vendorizing its dependencies. This is the
 from the rest of your system by vendorizing its dependencies. This is the
 recommended way of installing `poetry`.
 recommended way of installing `poetry`.
 
 
+### osx / linux / bashonwindows install instructions
 ```bash
 ```bash
 curl -sSL https://raw.githubusercontent.com/sdispater/poetry/master/get-poetry.py | python
 curl -sSL https://raw.githubusercontent.com/sdispater/poetry/master/get-poetry.py | python
 ```
 ```
+### windows powershell install instructions
+```powershell
+$(Invoke-WebRequest -Uri https://raw.githubusercontent.com/sdispater/poetry/master/get-poetry.py).Content | python
+```
 
 
 !!! note
 !!! note