add documentation on the camera views.

docs/apis.md

@@ -45,6 +45,7 @@ platforms, specifically Matrice, is in works.
 
 ## How to get images from drone?
 Here's a sample code. For more information, please see [DroneControlBase](https://github.com/Microsoft/AirSim/blob/master/AirLib/include/controllers/DroneControllerBase.hpp) class.
+See [Camera Views](camera_views.md) for information on the camera views and how to change them.
 
 ```
 int playWithImages() 

docs/camera_views.md

@@ -0,0 +1,29 @@
+# Camera Views
+
+The camera views that are shown on screen are the camera views you can fetch via the DroneControllerBase::getImageTypeForCamera API.
+Note that getImageTypeForCamera returns .png compressed images.
+
+![Cameras](images/cameras.png)
+
+From left to right is the depth view, segmentation view and the FPV view.  These views must be visible in order for
+getImageTypeForCamera to work.
+
+## Depth View
+
+The depth view provides a ground truth depth map image.  This depth is computed from the 3D model information and therefore can
+be used to test any other algorithm that tries to compute depth from the images.
+
+## Segmentation View
+
+This view randomly colors objects in the scene based on information on how the 3D model was built.  These colors are currently
+random, so they contain no semantic tagging.  For example, in the above picture the hedge in the forground is made up of separate
+hedge segments so each segment gets a different color as a result, even though it is the same type of hedge.
+
+If you want your Unreal environment to provide colors that are meaningful, then override FlyingPawn::setupStencilIDs() function or 
+assign proper values in CustomDepthStencilValue property in object browser window in Unreal Editor, then remove the random 
+assignment that is happening in AFlyingPawn::setStencilIDs.
+
+## FPV View
+
+This view is simulating a fixed forward pointing camera on the drone.  Note however, that this camera switchs places with the
+main game view if the user presses '[' or ']'.  

docs/sitl.md

@@ -77,6 +77,18 @@ Local position: x=-0.0326988, y=0.00656854, z=5.48506
 If the z coordinate is large like this then takeoff might not work as expected.  Resetting the SITL and simulation 
 should fix that problem.
 
+## No Remote Control
+
+If you plan to fly with no remote control, just using DroneShell commands for example, then you will need to set the
+following parameters to stop the PX4 from triggering "failsafe mode on" every time a move command is finished.
+
+````
+param set NAV_RCL_ACT 0
+param set NAV_DLL_ACT 0
+````
+
+NOTE: Do `NOT` do this on a real drone as it is too dangerous to fly without these failsafe measures.
+
 ## Using VirtualBox Ubuntu
 
 If you want to run the above posix_sitl in a `VirtualBox Ubuntu` machine then it will have a different ip address from localhost.