Edit doc custom keywords

[AntoineJac]

No description provided.

[bretg]

Thanks @AntoineJac -- would like to align this with the proposal at prebid/Prebid.js#3687

i.e. instead of

TargetingParams.addUserKeyword(key: "testUserKey", value: "testUserValue")
TargetingParams.addInvKeyword("my_key_inv", "my_value_inv");

it would be something like

TargetingParams.addUserData(key: "testUserKey", value: "testUserValue")
TargetingParams.addContextData(key: "testContext", value: "testContextValue")
TargetingParams.addKeywords(["mykw1", "mykw2"]);

[bretg]

@AntoineJac - is this PR still good considering the changes proposed for first party data in prebid/Prebid.js#3687 ?

[AntoineJac]

@bretg , not yet I will work on it this week or next week following the changes proposed by prebid/Prebid.js#3687

[AntoineJac]

Close this one as it will be know using context and user data!