[RFC] Version 0.90 release candidate (#4475)

* Release 0.90

* Add script to automatically generate acknowledgment

* Update NEWS.md

python-package/setup.py

@@ -54,4 +54,5 @@ setup(name='xgboost',
                    'Programming Language :: Python :: 3.5',
                    'Programming Language :: Python :: 3.6',
                    'Programming Language :: Python :: 3.7'],
+      python_requires='>=3.4',
       url='https://github.com/dmlc/xgboost')

python-package/setup_pip.py

@@ -64,4 +64,14 @@ setup(name='xgboost',
       # root directory for some machines, and cause confusions on building
       # data_files=[('xgboost', LIB_PATH)],
       distclass=BinaryDistribution,
+      license='Apache-2.0',
+      classifiers=['License :: OSI Approved :: Apache Software License',
+                   'Development Status :: 5 - Production/Stable',
+                   'Operating System :: OS Independent',
+                   'Programming Language :: Python',
+                   'Programming Language :: Python :: 3',
+                   'Programming Language :: Python :: 3.5',
+                   'Programming Language :: Python :: 3.6',
+                   'Programming Language :: Python :: 3.7'],
+      python_requires='>=3.4',
       url='https://github.com/dmlc/xgboost')

python-package/xgboost/VERSION

@@ -1 +1 @@
-0.83.dev0
+0.90