Previously both 'IPsec' and 'IPSec' are used. It is consistent.
In IETF we use 'IPsec' consistently and 'IPsec' looks a better choice.
This commit also updates unnecessary capitalizations like:
- IPsec Policy -> IPsec policy
- IKE Policy -> IKE policy
- IPsec Site Connection -> IPsec site connection
- VPN Service -> VPN service
In the horizon convention, every word is capitalized
only in page titles, action captions and field captions.
For other messages, there is no need to capitalize them.
Change-Id: I7f3ba10d5a7051fe598b45d13af79cc1ead0285f
Closes-Bug: #1713766