Add iceflow to list of python libs users may be interested in

Also move icepyx higher in the list

Author: trey-stafford

notebooks/altimetry_harmonization/0_introduction.ipynb

@@ -28,6 +28,9 @@
     "\n",
     "Some Python packages/libraries that users may consider investigating include:\n",
     "\n",
+    " * [iceflow](https://iceflow.readthedocs.io/en/latest/): a Python library that provides the ability to search, download, and access laser altimetry data from (pre-)Operation Icebridge and ICESat datasets.\n",
+    " * [*icepyx*](https://icepyx.readthedocs.io/en/latest/):\n",
+    " Library for ICESat-2 data users\n",
     " * [*geopandas*](https://geopandas.org/):\n",
     " Library to simplify working with geospatial data in Python (using pandas) \n",
     " * [*h5py*](https://github.com/h5py/h5py):\n",
@@ -36,8 +39,7 @@
     " Comprehensive library for creating static, animated, and interactive visualizations in Python\n",
     " * [*vaex*](https://github.com/vaexio/vaex):\n",
     " High performance Python library for lazy Out-of-Core dataframes (similar to *pandas*), to visualize and explore big tabular data sets\n",
-    " * [*icepyx*](https://icepyx.readthedocs.io/en/latest/):\n",
-    " Library for ICESat-2 data users\n",
+    "\n",
     "\n",
     "\n",
     "## **1.2 Learning Goals**\n",