Update the API guides for About Feature

Added the about guide for iOS

Change-Id: I1470125d536e47ea43f5a769f20841c2a8c5f96d
Signed-off-by: Nikhil Dabhade <ndabhade@qce.qualcomm.com>
ASADOC-14 Updated the About Interface definition

The DeviceName is no longer required.
Added clarification to specify the AppId must be 128-bit UUID

Cleaned up the tables for the Announce signal making is simpler
to under stand.

- Add the icon interface to the About Feature interface documentation
- Center aligned some values in the tables to improve readability
- Changed Inputs to Message Arguments
- Change Output to Return Arguments
- Add Error return for methods that have a known error return value
- changed the table for properties to from Writable to Read/Write since
  the possible values are Read Only, Write Only, and Read/Write not just
  yes and no.
- in a lot of locations I added tick marks to make the output use constant
  width font use for code.
- Added the input and output signatures to the Method names
- AppId Field name must start with capital A not lower case

This change addresses much more than ASADOC-14 it also covers ASADOC-16
and more.  This change was done without knowledge the tickets.

Change-Id: I18c9b3ef376bf16bbbea753a068001aa939120c1
Signed-off-by: George Nash <georgen@qce.qualcomm.com>