dscanner - Drozer based post-build dynamic vulnerability scanner command

* New command `dscanner`, enables one to scan signed APKs with Drozer
 * Drozer is a dynamic vulnerability scanner for Android
 * Drozer runs in a emulator or on-device, this new `dscanner` command...
  * starts a docker image with Drozer and the Android Emulator pre-installed,
  * loads the signed APK into the emulator
  * activates Drozer automated tests for the APK
  * gathers the report output and places it next to the original APK
 * The Drozer docker image can be:
  * cached locally for re-use (just don't run --clean*)
  * retrieved from dockerhub.com for more efficient runtime
  * or be built from scratch (in the new "./docker" directory)
 * New "Vulnerability Scanning" documentation section (run gendocs.sh)

docker/install_agent.py

@@ -0,0 +1,63 @@
+#!/usr/bin/env python2
+
+import os
+from subprocess import call, check_output
+from time import sleep
+
+FNULL = open(os.devnull, 'w')
+
+print("Ensuring device is online")
+call("adb wait-for-device", shell=True)
+
+print("Installing the drozer agent")
+print("If the device just came online it is likely the package manager hasn't booted.")
+print("Will try multiple attempts to install.")
+print("This may need tweaking depending on hardware.")
+
+
+attempts = 0
+time_to_sleep = 30
+
+while attempts < 8:
+    output = check_output('adb shell "pm list packages"', shell=True)
+    print("Checking whether the package manager is up...")
+    if "Could not access the Package Manager" in output:
+        print("Nope. Sleeping for 30 seconds and then trying again.")
+        sleep(time_to_sleep)
+    else:
+        break
+
+time_to_sleep = 5
+attempts = 0
+
+while attempts < 5:
+    sleep(time_to_sleep)
+    try:
+        install_output = check_output("adb install /home/drozer/drozer-agent.apk", shell=True)
+    except Exception:
+        print("Failed. Trying again.")
+        attempts += 1
+    else:
+        attempts += 1
+        if "Error: Could not access the Package Manager" not in install_output:
+            break
+
+print("Install attempted. Checking everything worked")
+
+pm_list_output = check_output('adb shell "pm list packages"', shell=True)
+
+if "com.mwr.dz" not in pm_list_output:
+    print(install_output)
+    exit("APK didn't install properly. Exiting.")
+
+print("Installed ok.")
+
+print("Starting the drozer agent main activity: com.mwr.dz/.activities.MainActivity")
+call('adb shell "am start com.mwr.dz/.activities.MainActivity"', shell=True, stdout=FNULL)
+
+print("Starting the service")
+# start the service
+call("python /home/drozer/enable_service.py", shell=True, stdout=FNULL)
+
+print("Forward dem ports mon.")
+call("adb forward tcp:31415 tcp:31415", shell=True, stdout=FNULL)