Upgrade cxxtest

[Yves]

Upgrade cxxtest to support new features like the XmlPrinter which is needed for Jenkins integration.

[Yves]

I have a working patch but creating something (an exe) without Python dependency for Windows is a bit difficult.

These steps work and I plan to repeat them in a Windows VM to create the final binary.

Install Python 2.7
Download pyinstaller (v2.1) from http://www.pyinstaller.org/ and extract it to D:\projects\build
Download and install http://sourceforge.net/projects/pywin32/files/pywin32/Build%20218/
D:\projects\build\pyinstaller\PyInstaller-2.1>C:\Python27\python.exe pyinstaller.py -p D:\projects\0ad\libraries\source\cxxtest-4.3\python
--hidden-import=cxxtest -F D:\projects\0ad\libraries\source\cxxtest-4.3\bin\cxxtestgen

[Yves]

In 14817:

Adds the unmodified sources for the new version of cxxtest as downloaded from here (I've removed the .gitignore and .cvsignore files):
​http://netcologne.dl.sourceforge.net/project/cxxtest/cxxtest/4.3/cxxtest-4.3.tar.gz

I'll patch these sources and remove the old version in later commits.

Refs #2450

[Yves]

In 14818:

Upgrades cxxtest.

Switches to the already committed new cxxtest sources and deletes the old sources.
Applies the changes from r7081 and r6258 to the updated sources.
Replaces the cxxtestgen.exe for Windows. This file was created from cxxtest's python script using pywin32.
Modifies update-workspace.sh to force a rebuild when cxxtest options could have been changed during the premake step.
Adds an additional option (--jenkins-tests) to premake4.lua/update-workspaces.sh to use cxxtest's XmlPrinter which generates output than can be used by Jenkins.

Fixes #2450