Improved package description in README.rst.

Signed-off-by: Daniel Scheffler <danschef@gfz-potsdam.de>

README.rst

@@ -2,7 +2,8 @@
 py_tools_ds
 ===========
 
-A collection of Python tools by Daniel Scheffler.
+A collection of geospatial data analysis tools that simplify standard operations when handling geospatial raster
+and vector data as well as projections.
 
 
 * Free software: GNU General Public License v3 or later (GPLv3+)