Create sample "malware" for demonstration

[georgeneokq]

Create a "malware" that helps to demonstrate what this tool can do. The malware should be built into a binary and be placed in the "external" folder in this repository. Documentation on what command line arguments to specify when using our tool should also be added after.

The malware should fulfill these requirements:

• [x] Accept command line arguments
• [x] Terminate after an ample amount of time to view changes made by the malware (or be specified by a command line argument)
• [x] Modify at least 2 existing registry values
• [x] Delete at least 2 existing registry keys
• [x] Delete at least 2 existing registry values
• [x] Add at least 2 new registry keys
• [x] Add at least 2 new registry values