Document the new time/dt/scheduling system (as if it were already implemented)
First steps towards the new scheduling system
Most problems fixed (except: recording from subgroups, changing dt for spikequeue)
Fix monitors (no need to use the source's clock, monitors can use their own clock)
Fix an overwritten `dt` attribute in `SynapticPathway.initialise_queue`
Use the floating point value of dt, not the `Quantity` as the key for the dictionary in `_determine_clocks` -- otherwise it won't work in Python3
Update some more tests to work with the new clock system.
Make sure that the order of objects in a `Network` is deterministic, even for arbitrary orderings (same dt, when and order attributes).
Don't hide failed `get_value()` calls in `AttributeValue` when transforming the variables dictionary into the final namespace.
Adapt the test that refers to `t` with a 0ms run to make sure that a clock exists.
Partly revert previous changes, establish the new clock/dt system as discussed in #318
Disallow setting `Network.t` directly.
Add a `clock` argument everywhere
Do not allow directly setting a clock's `t` attribute. Also make the internal integer timestep a protected attribute.
Only allow dt changes that are compatible with an integer representation of the current time.
Only forward pure numpy arrays to numpy's where function, otherwise it fails in numpy 1.9
Update the docstrings and default values for the scheduling arguments of most objects.
Update the docstrings and default values for the scheduling arguments of `SpatialNeuron`
Update the user documentation on scheduling.

[ci skip]
Implement a store/restore mechanism for resetting object states to earlier values. Not yet working for the C version of the SpikeQueue (and standalone)