Several project setup fixes

[michaelbrooks]

I ran into several issues getting this to run, so here's what I had to fix:

• the shell scripts should be forced to LF. I ran this in Vagrant on Windows, so the CRLF endings from my Windows git clone made the script un-runnable in Ubuntu.
• the README needs to mention installing the python requirements
• the README refers to start.sh which at some point must have been renamed to just start
• sample_python_app.py tries to save a config file but was using read mode instead of write
• the relative path to the log directory is outside the project folder. In Vagrant, for example, this becomes the absolute path /log, which isn't writable.
• the bootstrap.sh file should use the -y flag when running apt-get. It should also install curl before using curl to install pip.

I wasn't able to actually test whether the program streams data from Gnip correctly because I found out my access doesn't include the streaming APIs, but it at least ran after these changes.