Simplify and fix pyspark script.

This patch removes compatibility for IPython < 1.0 but fixes the launch
script and makes it much simpler.

I tested this using the three commands in the PySpark documentation page:

1. IPYTHON=1 ./pyspark
2. IPYTHON_OPTS="notebook" ./pyspark
3. IPYTHON_OPTS="notebook --pylab inline" ./pyspark

There are two changes:
- We rely on PYTHONSTARTUP env var to start PySpark
- Removed the quotes around $IPYTHON_OPTS... having quotes
  gloms them together as a single argument passed to `exec` which
  seemed to cause ipython to fail (it instead expects them as
  multiple arguments).

1 files changed, 3 insertions, 2 deletions

diff --git a/docs/python-programming-guide.md b/docs/python-programming-guide.md
index dc187b3efe..c4236f8312 100644
--- a/docs/python-programming-guide.md
+++ b/docs/python-programming-guide.md
@@ -99,8 +99,9 @@ $ MASTER=local[4] ./bin/pyspark
 
 ## IPython
 
-It is also possible to launch PySpark in [IPython](http://ipython.org), the enhanced Python interpreter.
-To do this, set the `IPYTHON` variable to `1` when running `bin/pyspark`:
+It is also possible to launch PySpark in [IPython](http://ipython.org), the 
+enhanced Python interpreter. PySpark works with IPython 1.0.0 and later. To 
+use IPython, set the `IPYTHON` variable to `1` when running `bin/pyspark`:
 
 {% highlight bash %}
 $ IPYTHON=1 ./bin/pyspark