Compiling touchlib on Ubuntu 11.04

In the event that it might be useful for someone, here's how to compile touchlib on Ubuntu 11.04:

Install some dependencies and utils:

sudo apt-get install cmake libcv2.1 libcvaux2.1 libcv-dev libcvaux-dev libglut3 fftw-dev g++ libxmu-dev libglut3-dev libhighgui-dev subversion

Check out the code into the 'multitouch' directory:
```
svn co http://touchlib.googlecode.com/svn/trunk/ multitouch
```
NB: we recieved revision 403.
Change into the new directory:
```
cd multitouch
```
Fix an include problem: Add the line
```
#include <stdio.h>
```
to the top of
```
src/RectifyFilter.cpp
```
Tell the build script where to find the libraries:
```
export OpenCV_ROOT_DIR=/usr/
```
Create the build scripts:
```
cmake .
```
Build and compile:
```
make
```