security.md: Edit for consistent use of leading statement throughout technical capabilities document. Included sub-category section headers. Reworded to clarify other statements. Removed "for the IOT device" throughout to be consistently worded with other capabilities categories.
security.md: Edit for consistent use of leading statement throughout technical capabilities document. Included sub-category section headers. Reworded to clarify other statements. Removed "for the IOT device" throughout to be consistently worded with other capabilities categories.