remove demos and add examples

Signed-off-by: varun-r-mallya <varunrmallya@gmail.com>

examples/pybpf0.py

@@ -0,0 +1,35 @@
+from pythonbpf import bpf, section, bpfglobal, BPF
+import sys
+from ctypes import c_void_p, c_int64
+
+# Instructions to how to run this program
+# 1. Install PythonBPF: pip install pythonbpf
+# 2. `sudo /path/to/venv/bin/python ./python-bpf/demo/pybpf0.py`
+
+@bpf
+@section("tracepoint/syscalls/sys_enter_execve")
+def hello_world(ctx: c_void_p) -> c_int64:
+    print("Hello, World!")
+    return c_int64(0)
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"
+
+b = BPF()
+b.load_and_attach()
+
+def main():
+    try:
+        with open("/sys/kernel/debug/tracing/trace_pipe", "r") as f:
+            for line in f:
+                sys.stdout.write(line)
+                sys.stdout.flush()
+    except KeyboardInterrupt:
+        pass
+    except PermissionError:
+        sys.stderr.write("Need root privileges to read trace_pipe\n")
+
+if __name__ == "__main__":
+    main()