reorder installation doc sections
reorder installation doc sections

closes #265

apiato/apiato,Porto-SAP/Hello-API,apiato/apiato,Porto-SAP/Hello-API,Porto-SAP/Hello-API,Mohammad-Alavi/Samandoon,Mohammad-Alavi/Samandoon,apiato/apiato,Mohammad-Alavi/Samandoon,Mahmoudz/Hello-API,Mahmoudz/Hello-API,Mohammad-Alavi/Samandoon