Update README with links to docs and new dependencies

README.md

@@ -1,9 +1,12 @@
-# hera_pspec
+# ``hera_pspec``: HERA delay spectrum estimation
 
 [![Build Status](https://travis-ci.org/HERA-Team/hera_pspec.svg?branch=master)](https://travis-ci.org/HERA-Team/hera_pspec)
 [![Coverage Status](https://coveralls.io/repos/github/HERA-Team/hera_pspec/badge.svg?branch=master)](https://coveralls.io/github/HERA-Team/hera_pspec?branch=master)
+[![Documentation](https://readthedocs.org/projects/hera-pspec/badge/?version=latest)](https://readthedocs.org/projects/hera-pspec/badge/?version=latest)
 
-**hera_pspec description**
+The ``hera_pspec`` library provides all of the tools and data structures needed to perform a delay spectrum analysis on interferometric data. The input data can be in any format supported by ``pyuvdata``, and the output data are stored in HDF5 containers.
+
+For usage examples and documentation, see http://hera-pspec.readthedocs.io/en/latest/.
 
 ## Installation
 
@@ -15,6 +18,8 @@
 * scipy >= 0.19
 * astropy >= 2.0
 * hera_cal (https://github.com/HERA-Team/hera_cal.git)
+* pyyaml
+* hdf5
 
 For anaconda users, we suggest using conda to install astropy, numpy and scipy.
 
@@ -24,7 +29,4 @@ Clone the repo using
 
 Navigate into the directory and run `python setup.py install`.
 
-## Package Details and Usage
-
-