[!7] Resolve "Add analytic jacobians"

Merge branch '5-add-analytic-jacobians' into 'master'

ref:copasi/dune-copasi

### What does this MR do?

It implements anaylitic jacobians for volume and skeleton integrals in the
local operator. Additionally it add installation rules for CMake.

### Is there something that needs to be double checked?

<!-- Is there something a reviewer should look out for _especially_? -->

No.

### Can this MR be accepted?

-   [x] Implemented
    -   [x] jacobian_volume
    -   [x] jacobian_skeleton
-   [x] Added tests:
    -   [x] Both numerical and analyitical jacobians are tested against a
        reference solution.
-   [ ] Pipelines passing <!-- please check for new warnings -->
     <!-- change all occurences of <branch> for your branch name -->

    -   [ ] [![Build Status]]
    -   [ ] [![Build Status][1]]
    -   [ ] [![Build status][2]]

-   [x] Delete branch option set <!-- unless there's a good reason -->

### Related issues

Closes [#5]

<!-- For automatic closing, do not forget the commas between issue numbers-->

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See merge request [!7]

  [Build Status]: https://gitlab.dune-project.org/copasi/dune-copasi/badges/5-add-analytic-jacobians/pipeline.svg
  [![Build Status]]: https://gitlab.dune-project.org/copasi/dune-copasi/pipelines
  [1]: https://travis-ci.org/SoilRos/dune-copasi.svg?branch=5-add-analytic-jacobians
  [![Build Status][1]]: https://travis-ci.org/SoilRos/dune-copasi
  [2]: https://ci.appveyor.com/api/projects/status/6605joy2w17qvca8/branch/5-add-analytic-jacobians?svg=true
  [![Build status][2]]: https://ci.appveyor.com/project/SoilRos/dune-copasi/branch/5-add-analytic-jacobians
  [#5]: gitlab.dune-project.org/NoneNone/issues/5
  [!7]: gitlab.dune-project.org/copasi/dune-copasi/merge_requests/7


Closes #5