Server certificate trust, code review fixes

Added empty certificate trust store.
Now server certificate trust checks follow this order:
1) If "res/raw/client_truststore.bks" is not empty, use it as the
   pinned cert trust store (default is empty)
2) Otherwise, if the "Show certificate dialog" developer preference
   is enabled, use that (default is disabled)
3) Otherwise, use the default system trust store, consists of
   normal trusted Android CA certs
Also fixed typo in comment in SVMPAppRTCClient.
Note: the empty trust store can be replaced with one of your
choosing. The password to access that trust store should be set
accordingly in Constants.java.

Change-Id: Ifa799a7e858ff5f0d2413568236c19a169206a05
Clean up some stale code and comments

Change-Id: I535413ed85a6d0254bba2e6324cb624cc49865b2
More accurate VMREADY wait state error

Print a more useful error message when the server fails during the
stage where it's waiting on the VM. This usually indicates a networking
problem between the svmp-server and the Android VM.

Change-Id: I533bcfa69fcfaeb7bd984abfdb0e56f260b7a5a3
Bump version number to 1.3

Change-Id: I96e91f714f1bd185327e8f8bef53e659061e2ec9