Resolve "lr_decay should be optional"

See merge request toar/machinelearningtools!73

Resolve "Update custom_objects to reload models"

See merge request toar/machinelearningtools!70

closes #77, #78

See merge request toar/machinelearningtools!69

Resolve "Minimal sample size in  train-, val, test-set"

See merge request toar/machinelearningtools!68

apply bug fix to dev too

See merge request toar/machinelearningtools!67

apply bugfix to dev branch too

See merge request toar/machinelearningtools!65

Resolve "BUG: wrong model plot path"

Closes #70

See merge request toar/machinelearningtools!64

apply bugfix to dev branch too

See merge request toar/machinelearningtools!63

Resolve "BUG in check valid stations"

Closes #69

See merge request toar/machinelearningtools!62

Develop

Closes #48, #49, #50, #51, #52, #59, #20, #61, #64, #65, #62, #67, and #68

See merge request toar/machinelearningtools!59

/close #68

See merge request toar/machinelearningtools!60

/close #67

See merge request toar/machinelearningtools!58

# Conflicts:
#	test/test_model_modules/test_inception_model.py

/close #65

See merge request toar/machinelearningtools!55

update requirements to get cartopy running

See merge request toar/machinelearningtools!56