Add a test function to brian2, i.e. you can call brian2.test() to run
the test suite
Add some guidelines for writing tests
Added docs on preferences
Merge branch 'master' of https://github.com/brian-team/brian2.git
Add some documentation for the current development workflow
Reading preference files
preference validation functions
Replaced old preferences stuff throughout Brian, including sphinxext
Forgot to put in previous commit: added core.core_preferences file,
where you should define the core preferences
Added tool to automatically generate default_preferences file, should be
run before any new release
Allow file object instead of filename in read_preference_file
Various changes to preferences
* Changed preferences to use values rather than strings
* put everything into BrianGlobalPreferences
* changed validation functions (default validators are back)
* derived BrianGlobalPreferences from MutableMapping
Warning on Network.run if unvalidated preferences set
Added preference tests and fixed a bug
Some minor docstring and style changes, removed unused imports.
Merge pull request #6 from brian-team/preferences

new preference system, fixes #5
Added script to run tests (for running from eclipse easily)
Shift everything around, move some responsibility to codegen (only
Python works for now)
Make CPP code generation work again with the new system
Merge master branch (with the new preferences system)

Conflicts:
	brian2/groups/neurongroup.py