Create PackageManifest classes for NPM

Creates PackageManifest classes for NPM manifests
and overrides detection and PackageMamanifest creation methods.

Signed-off-by: Ayan Sinha Mahapatra <ayansmahapatra@gmail.com>

Author: AyanSinhaMahapatra

src/packagedcode/__init__.py

@@ -51,7 +51,9 @@
     models.Axis2Mar,
 
     about.Aboutfile,
-    npm.NpmPackage,
+    npm.NPMPackageJSON,
+    npm.NPMPackageLockJSON,
+    npm.NPMYarnLockJSON,
     phpcomposer.PHPComposerPackage,
     haxe.HaxePackage,
     cargo.RustCargoCrate,

src/packagedcode/models.py

@@ -861,6 +861,7 @@ def get_package_root(cls, manifest_resource, codebase):
 class CpanModule(Package, PackageManifest):
     file_patterns = (
         '*.pod',
+        # TODO: .pm is not a package manifest
         '*.pm',
         'MANIFEST',
         'Makefile.PL',