Add requirements.txt with critically vulnerable dependencies

[Austin Becker (AustinJayBecker)]

Adding vulns:

Package	Version	CVE	Severity
Pillow	8.2.0	CVE-2021-34552	CRITICAL – buffer overflow / arbitrary code execution
PyYAML	5.1	CVE-2020-14343	CRITICAL – arbitrary code execution via unsafe YAML load
Django	2.2.0	CVE-2021-35042	CRITICAL – SQL injection via QuerySet.order_by()
urllib3	1.24.1	CVE-2019-11324	CRITICAL – certificate verification bypass