added short install guide

docs/install.rst

@@ -2,4 +2,64 @@
 Installation
 ============
 
-todo
+This guide assumes that the user has already installed anaconda.
+
+ASAP requires that Install both Ames Stereo Pipeline and ISIS are available to the user in the PATH.
+There are several ways to do this outside of this guide's scope, but a simple solution is to use the 
+following conda environment YAML configuration file:
+
+.. code-block:: yaml
+
+   name: asap_0_0_4
+   channels:
+     - nasa-ames-stereo-pipeline
+     - usgs-astrogeology
+     - conda-forge
+     - defaults
+   dependencies:
+     - python=3.6
+     - stereo-pipeline==2.7.0
+     - nb_conda_kernels
+     - jupyterlab
+     - requests
+     - fire
+     - tqdm
+     - sh
+     - papermill
+     - pip 
+     - pip:
+       - rasterio
+       - pyproj
+       - moody>=0.0.4
+       - asap_stereo>=0.0.4 
+
+
+Using the command::
+
+    conda env create  --file asaptest.yml
+
+Will create a new conda environment called "asap_0_0_4". 
+At this point, ASAP will be available to the user.
+However, the user must download the `ISIS Data Area  <https://github.com/USGS-Astrogeology/ISIS3#the-isis-data-area>`_ 
+and run the `ISIS variable initialization script <https://github.com/USGS-Astrogeology/ISIS3#isis-installation-with-conda>`_
+to finish the installation. Steps for these last two steps are available in the ISIS README and documentation linked to before. 
+Be sure to run the variable initialization script in your new conda environment by first running:: 
+
+    conda activate asap_0_0_4
+
+and then::
+
+    python $CONDA_PREFIX/scripts/isis3VarInit.py <any args...>
+
+Deactivate, then reactivate the environment, and you are ready to start using asap! 
+
+To test if asap is installed correctly, run each of the following::
+
+    asap
+    asap ctx
+    asap hirise
+    asap common
+    
+Each of these commands should show the help page for the asap modules and shouldn't print any errors.
+
+