update version to 0.4.0

Author: CunliangGeng

CHANGELOG.md

@@ -4,6 +4,13 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
+## 0.4.0
+
+- Added `many2sql` to support read multiple PDB files
+- Added support for `Path` objects of input PDB files
+- Added support for `help(pdb2sql)`
+- Updated assignment of chain IDs in `StructureSimilarity`
+
 ## 0.3.0
 
 - Added `align` to superpose a structure to a specific axis or plane

pdb2sql/__version__.py

@@ -1 +1 @@
-__version__ = '0.3.0'
+__version__ = '0.4.0'