Some minor docstring/readme updates

README.md

@@ -26,12 +26,12 @@
 
 Install with pip from PyPi (preferred):
 ```bash
-pip install fatamorgana
+pip3 install fatamorgana
 ```
 
 Install directly from git repository:
 ```bash
-pip install git+https://mpxd.net/code/jan/fatamorgana.git@release
+pip3 install git+https://mpxd.net/code/jan/fatamorgana.git@release
 ```
 
 ## Documentation

fatamorgana/__init__.py

@@ -16,7 +16,13 @@
 
  Dependencies:
     - Python 3.5 or later
-    - numpy (optional, no additional functionality)
+    - numpy (optional, faster but no additional functionality)
+
+ To get started, try:
+ ```python3
+    import fatamorgana
+    help(fatamorgana.OasisLayout)
+ ```
 """
 import pathlib