Makes for a more precise Hessian matrix when using automatic differentiation.

[[Imported from SVN: r9425]]

[[Imported from SVN: r9424]]

[[Imported from SVN: r9423]]

[[Imported from SVN: r9422]]

[[Imported from SVN: r9421]]

[[Imported from SVN: r9420]]

[[Imported from SVN: r9419]]

Hence many input configurations are tested now

[[Imported from SVN: r9418]]

They are easier to debug

[[Imported from SVN: r9417]]

[[Imported from SVN: r9416]]

[[Imported from SVN: r9415]]

Because it may contain a projection onto the manifold, which
is part of the energy evaluation if we view the energy as
being defined on all of R^n (as ADOL-C does).

[[Imported from SVN: r9414]]

[[Imported from SVN: r9413]]

Not actually working yet, though.

[[Imported from SVN: r9412]]

[[Imported from SVN: r9411]]

[[Imported from SVN: r9410]]

[[Imported from SVN: r9409]]

[[Imported from SVN: r9408]]

[[Imported from SVN: r9407]]

[[Imported from SVN: r9406]]

[[Imported from SVN: r9405]]

[[Imported from SVN: r9404]]

[[Imported from SVN: r9403]]

[[Imported from SVN: r9402]]

The only exception is the material parameters.  ADOL-C (for which
we are doing this), doesn't need to have them in a special type.

[[Imported from SVN: r9401]]

Saves us one call to sqrt().

[[Imported from SVN: r9400]]

[[Imported from SVN: r9399]]

This is needed to use the ADOL-C automatic differentiation library.

[[Imported from SVN: r9398]]

[[Imported from SVN: r9397]]

[[Imported from SVN: r9396]]

[[Imported from SVN: r9395]]

[[Imported from SVN: r9394]]

[[Imported from SVN: r9393]]

[[Imported from SVN: r9392]]

[[Imported from SVN: r9391]]

[[Imported from SVN: r9390]]

[[Imported from SVN: r9389]]

[[Imported from SVN: r9388]]

[[Imported from SVN: r9387]]

Because ADOL-C cannot handle the latter

[[Imported from SVN: r9386]]