add version number to __init__

Author: bwheelz36

bayes_opt/__init__.py

@@ -4,6 +4,8 @@
 from .logger import ScreenLogger, JSONLogger
 from .constraint import ConstraintModel
 
+__version__ = 1.3.0
+
 __all__ = [
     "BayesianOptimization",
     "ConstraintModel"
@@ -13,3 +15,4 @@
     "JSONLogger",
     "SequentialDomainReductionTransformer",
 ]
+