tree export_graphviz: remove unused close parameter and close the file if out_file is a string
Merge pull request #2394 from ndawe/export_graphviz

[MRG] tree export_graphviz: unused close parameter
DOC clarify distances in KMeans' _labels_inertia
BUG: Remove UTF8 character

UTF8 characters break some IDEs and are hell to debug. We
should never set the encoding of our files