ALLJOYN-2215 Suppress C4244 and C4267 warnings from MSVC

Now that we have turned on warning level /W3 we are suppressing these two warnings
in addition to the already suppressed warnings.

C4244 - is for conversion from one data type to a smaller data type like int32
to int16 it may be worth investigating these errors in the future but for now
the are going to be suppressed

C4267 - similar to the C4244 warning except this is specifically related to
using the size_t data type.  once again it may be worth investigating these
error in the future but for now they are going to be suppressed.

Change-Id: I95d192e2552dfd92202eeacb6aaea45158a52b66