Added ability to select code signing identity (and if required profile).

For the safariLauncher for real devices you can now use the following command to run reset.sh and build safari launcher:

./reset.sh --ios --real-safari --code-sign <b>\<code sign identity (e.g.  'iPhone Developer')></b>
or 
./reset.sh --ios --real-safari <b>--code-sign \<code sign identity>  --profile '\<profile (e.g. AAAAA123-BBBB-AAAA-AAAAAAA)>'</b>

if neither are provided then default code sign identity will be set to 'iPhone Developer'. Code sign is mandatory, profile is optional (as it will automatically pick one base on code sign identity).

After this I will look to update the docs related to the Safari Launcher changes.