Rename AdaptiveAuth and move to security package

Rename AdaptiveAuthService to AdaptiveAuthenticationService and nest in
security package, rename packages from adaptive auth to adaptive
authentication. Leaving flags package as is, since the package name is
part of the flag identifier.

Test: atest AdaptiveAuthenticationServiceTest
Flag: NONE renaming files
Bug: N/A
Change-Id: I38fb343b483e4d818707aefe15a2b07c888cd6f0