fix(FEC-8096): some of OTT metadata is getting overriden

[odedhutzler]

Description of the Changes

changed the current structure of the metadata:

{
   0: {key: "someKey",
     value: "someValue"
    },
   1: {key: "someKey",
        value: "someValue"
    },
   2: {key: "someKey",
    value: "someValue"
    },
..
}

to

metas: {
  key1: value,
  key2: value,
...
},
tags: {
  key1: value,
  key2: value,
...
}

• this also resolves the bug that some of the metas got overridden.

CheckLists

• changes have been done against master branch, and PR does not conflict
• new unit / functional tests have been added (whenever applicable)
• test are passing in local environment
• Travis tests are passing (or test results are not worse than on master branch :))
• Docs have been updated