Update README to better reflect reality.  Change "trusted"/"untrusted" language to "debug"/"release"
Update README to better reflect reality.  Change "trusted"/"untrusted"
language to "debug"/"release"

Review URL: http://codereview.chromium.org/1376004

git-svn-id: e22621a84199d42b34715cdc089545aeedbbf23f@46 050acbb0-2703-11df-ab0a-9f3f633ae91d

sbc100/nativeclient-sdk,sbc100/nativeclient-sdk,sbc100/nativeclient-sdk,sbc100/nativeclient-sdk,sbc100/nativeclient-sdk,sbc100/nativeclient-sdk,sbc100/nativeclient-sdk