v0.1.2

TsyganenkoModels v0.1.2

Diff since v0.1.1

Merged pull requests:

• feat: model interface (#11) (@Beforerr)
• refactor: integrate with GeoCotrans ExternalFieldModel interface and add EarthMagneticField composite model (#13) (@Beforerr)
• feat: add TsyIGRF composite model combining IGRF and Tsyganenko external fields (#14) (@Beforerr)