update README and setup description

Author: tobyroseman

README.md

@@ -41,7 +41,7 @@ We release an updated version about once every 1.5 months or so. You can downloa
 the most recent version directly from [pypi](https://pypi.python.org/pypi/SFrame)
 or using pip:
 
-    pip install sframe
+    pip install -U sframe
 
 **Requirements**
 

oss_src/unity/python/setup.py

@@ -160,7 +160,7 @@ def run(self):
             exclude=["*.tests", "*.tests.*", "tests.*", "tests", "*.test", "*.test.*", "test.*", "test"]),
         url='https://dato.com',
         license='LICENSE.txt',
-        description='SFrame enables developers and data scientists to apply machine learning to build state of the art data products.',
+        description='SFrame is an scalable, out-of-core dataframe, which allows you to work with datasets that are larger than the amount of RAM on your system.',
         # long_description=open('README.txt').read(),
         classifiers=classifiers,
         install_requires=[