Change cpl formulation to have r13 as default

- Make r13 as default to have be†ter readability
- Needed a change in lienar solver
  - Because indefinite system yields different solution with mumps, now use umfpack
- In general, for non-inflow conditions, we have non unique solution because of pressure
  - Solvers can therefore differ in results (is bad)
3 jobs for feat/symmetrization in 28 minutes and 14 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #580339
build:doc

00:00:48

manual #580338
allowed to fail manual
build:environment
 
  Test
passed #580340
test:pytest

00:27:25

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