4 - Create SBOM-generators for languages that use lockfiles

Proposal

After 2 - Create language-specific SBOM-generator for Go (#364870 - closed) has been completed, we'll have a pattern for structuring individual language-specific SBOM generators.

The purpose of this issue is to create SBOM generators for the rest of the supported languages that use lockfiles to generate dependency information:

• PHP
• C
• C++
• JavaScript
• .NET
• C#

The SBOM generators for .NET, C# and JavaScript do not need to export dependency graph information, since that will be handled by Add dependency graph information to Gemnasium's... (#366168 - closed).