Added Invoke-ReflectivePEInjection

Another awesome addition from Joe Bialek. Invoke-ReflectivePEInjection
is a vast improvement over Invoke-ReflectiveDllInjection. It adds the
following features:

* Now supports loading exe files in memory
* Supports reflective dll injection into a remote process
* Additional sample Visual Studio solutions

CodeExecution/Invoke-ReflectivePEInjection_Resources/Shellcode/x64/ExitThread.asm

@@ -0,0 +1,14 @@
+[SECTION .text]
+
+global _start
+
+_start:
+	; Set a var to 1, let PS known exe is exiting
+	mov rbx, 0x4141414141414141
+	mov [rbx], byte 0x01
+
+	; Call exitthread instead of exitprocess
+	sub rsp, 0xc0
+	and sp, 0xFFf0 ; Needed for stack alignment
+	mov rbx, 0x4141414141414141
+	call rbx