GitLab

* add print and summary S3 method

* correct wrong signature

* attempt at bypassing linter

* Update R-package/R/lgb.Booster.R
Co-authored-by: James Lamb <jaylamb20@gmail.com>

* Update R-package/src/lightgbm_R.h
Co-authored-by: James Lamb <jaylamb20@gmail.com>

* Update include/LightGBM/c_api.h
Co-authored-by: James Lamb <jaylamb20@gmail.com>

* add more tests

* linter

* don't pluralize single tree

* remove duplicated function

* update changed function name

* missing declaration

* Update lightgbm_R.h

* Update R-package/tests/testthat/test_lgb.Booster.R
Co-authored-by: James Lamb <jaylamb20@gmail.com>

* accommodate custom objectives in print

* linter

* linter
Co-authored-by: James Lamb <jaylamb20@gmail.com>