v0.1.1

Changelog for v0.1.1

• Make some changes to tungsten and aluminum models to be more consistent with
  the use of minus signs in different operators: move minus sign from peak
  function to opCk operator (commits 8685f7a and b4392b3).
• Bug fixes and changes in CMakeLists.txt: conditionally install nlohmann_json
  headers (issue #16), do not add RPATH to binaries when installing them,
  (commit 6c91de3) and also install binaries to INSTALL_PREFIX/bin (issue #14).
• Start using clang-format in the project (ci pipeline). (Issue #43)
• Add possibility to add initial and boundary conditions to fields with other
  name than "default". (Commit c65fb23)
• Add schema file for the input file. (Commit 6eeeab9)
• Fix license headers in source files, add license header checker to GH Action
  and in general improve licensing information. (Issues #25, #39, #40)
• Replace #pragma once with a proper include guard in all header files. (Issue
  #48)
• Fix bug with clang-tidy configuration preventing compilation. (Issue #52)
• Major updates to README.md: update citing information, add description of
  application structure, add new images, scalability results, and add example
  simulation of Cahn-Hilliard equation. (Issues #5, #19, #22, #23, #27, #28,
  #40)