Annarchy

* The Euler implicit method is added.
* Systems of equations are now solved concurrentely.

* Early-stopping of simulations (simulate_until).

* Added hybrid populations (Spike2RatePopulaton, Rate2SpikePopulation).
* Individual save/load of populations and projections.
* PopulationViews can be used to build Projections.
* CSR objects are simplified.
* Default conductance behaviour (g_target = 0.0).
* Random distribution objects can take global parameters as arguments.
* min and max bounds can depend on other variables.
* Logical operators (and, or..) can be used in conditions.

* Rate-coded neurons must output "r", not "rate". Synapses must use "w", not "value".
* Synapses can access pre-synaptic weighted sums (pre.sum(exc)).
* Created PoissonPopulation.

* Connectivity matrices are now created in Cython.
* Recording methods have changed.
* Spiking neurons have a refractory period.
* Added clip() functions for semi-linear transfer functions.
* Added smoothed_firing_rate() method for visualizing spiking networks.

* First stable release with both rate-coded and spiking networks.