get rid of >=x.y.* non pep 508 compliant version spec in pandas

and loosen version of selfies and crem.

setup.py

@@ -4,13 +4,13 @@
 setup(name='deriver',
       description='Deriver: for all your molecule generation needs.',
       long_description='A software tool for the generation of novel chemical entities.',
-      version='2.7.4',
+      version='2.7.5',
       url='https://github.com/cyclica/deriver',
       license='All Rights Reserved Cyclica Inc.',
       packages=find_packages('src'),
       package_dir={'': 'src'},
       include_package_data=True,
       zip_safe=False,
-      install_requires=["selfies==1.0.1", "peewee>=3.9.3", "numpy>=1.16.3",
-                        "crem==0.2.4", "loguru>=0.4.1", "pandas>=1.0.*"]
+      install_requires=["selfies>=1.0.1", "peewee>=3.9.3", "numpy>=1.16.3",
+                        "crem>=0.2.4", "loguru>=0.4.1", "pandas>=1.0"]
       )