v0.3.15

Trixi v0.3.15

Diff since v0.3.14

Closed issues:

• Issues with final saving in OrdinaryDiffEq.jl (#453)

Merged pull requests:

• Extend plotting to 1D (#448) (@FelipeSantillan)
• Implement acoustic perturbation equations (#450) (@lchristm)
• bump compat bounds for OrdinaryDiffEq.jl; closes #453 (#454) (@ranocha)
• Try re-enabling codecov & fixing parallel builds for coveralls (#456) (@sloede)