Comply to Rust 0.12 warning about snake_case

```
more_pipes.rs:13:10: 13:26 warning: variable `fromParentSender` should have a snake case name such as `from_parent_sender`, #[warn(non_snake_case)] on by default
more_pipes.rs:13     let (fromParentSender, fromParentReceiver) = channel();
                          ^~~~~~~~~~~~~~~~
```
Update code sample for chapter 3.
Update code sample for chapter 11.
Update code sample for chapter 9.
Merge pull request #106 from vrinek/patch-1

Comply to Rust 0.12 warning about snake_case
Merge pull request #107 from jbcrail/update-ch03-sample

Update code sample for chapter 3.
Merge pull request #108 from jbcrail/update-ch09-sample

Update code sample for chapter 9.
Merge pull request #109 from jbcrail/update-ch11-sample

Update code sample for chapter 11.