Fix Doc8 errors

Fix Doc8 errors

Issue-ID: DCAEGEN2-197
Change-Id: I7de01b8c52ae7919f3d8d4f6545a53b026096ab9
Signed-off-by: Morgan Richomme <morgan.richomme@orange.com>
DOC: release notes updates

Change-Id: I8d88d65c1c5be9e114b6aab60d70b6e36464a75f
Issue-ID: DCAEGEN2-194
Signed-off-by: Vijay <vv770d@att.com>
Fix editorial errors

Modify ONPA by ONAP
Correct some JSON file example
Add code-block for code snippet

Change-Id: Ia313b6adc615bcd353f4e3c3e363c3f854d25181
ISSUE-ID: DCAEGEN2-199
Signed-off-by: Eric Debeau <eric.debeau@orange.com>
Improve documentation

Issue-Id: DCAEGEN2-199
Change-Id: Id5e3f3e57e86debe41b7df7986c9d8a808b2752f
Signed-off-by: Lusheng Ji <lji@research.att.com>
Cherry pick from master, add defaultbranch

Issue-ID: DCAEGEN2-206
Change-Id: I363a9331afa1bad33586aa2de34af9c3e6716532
Signed-off-by: Lusheng Ji <lji@research.att.com>