v0.2.1

KrylovPreconditioners v0.2.1

Diff since v0.2.0

Merged pull requests:

• Use AMDGPU.jl 0.8.2 (#40) (@amontoison)
• Add triangular operators for AMD and NVIDIA GPUs (#41) (@amontoison)
• Release 0.2.1 (#42) (@amontoison)