Fix as_float_array behaviour when copy=True
Add test of the as_float_array behaviour when copy=True
Add a copy parameter to safe_asarray()
Imp readability
doc: hedge the use of OOB estimates
ENH : removing warnings from tests in cd linear models
Merge pull request #2194 from NicolasTr/as_float_array_copy

[MRG] as_float_array doesn't copy
Refactored verbose output in GBRT - output much more nice
Added tests for verbose output in GBRT
cosmit: use str.format instead of %
updated whats new with GBRT changes