Adding example file for inhomogeneous parameters
Merge branch 'master' into development

* master:
  Update HISTORY.md
  Updating docs
Initial version of v2beta3 schema
Adding very preliminary NeuroML 2 files to HTML XSL file
Update README.md
Moving all of the LEMS examples out of NeuroML2CoreTypes to LEMSexamples

Updating NML2 examples to use beta3 schema
Schema: Making erev required in <channelDensity>

If erev is calculated from internal/external concs, use
<channelDensityNernst>
test.py updated to reflect restructureing of LEMSexamples etc.
Rmoving <reversalPotential> element until there's a working example that
needs it.
Adding type gateHHratesTauInf, for when alpha, beta, tau & inf are all specified (& tau depends on alpha/beta but not inf)

e.g. see here:
https://github.com/OpenSourceBrain/L5bPyrCellHayEtAl2011/blob/master/neuroConstruct/generatedNeuroML2/Nap_Et2.channel.nml
This was generated from:
https://github.com/OpenSourceBrain/L5bPyrCellHayEtAl2011/blob/master/neuroConstruct/cellMechanisms/Nap_Et2/NaChannel_HH.xml
Improved specification of dimensions in point3DWithDiam and forwardTransition
Increasing the types of biomodels qualifiers allowed.
Adding element Property with tag/value as used in NeuroML v1.x, which can be used in Annotation
Allowing property type in annotations
Adding in all the options for qualifiers from http://co.mbine.org/standards/qualifiers
Tidy up standard example
Folder for the results of simulations run with LEMS
Ignoring generated files
Adding Neuron unit ohm cm

Fixes #30
Adding saving of traces for ex5
Removing spurious 1e-5 factor in voltageClamp and renaming parameter seriesResistance

Renamed to simpleSeriesResistance to ensure old form with extra factor
not incorrectly used.
Tidied up examples using this
Updating schema & example for new form of voltageClamp