Fixed minor typos in C-interfaces; added feature for the "explicit" interfaces that distinguishes host and GPU allocated arrays (currently only for cuda and hip). Added C-tests for eigenvalues, cholesky, hermitian_multiply. Added Fortran and C-test for invert_triangular. Added device pointer (d_ptr) API tests. Added C-interface/C-test and fixed man page for elpa_solve_tridiagonal.