add locale angular code example

Example 1: i18n angular

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      <span i18n>Updated: {minutes, plural,
  =0 {just now}
  =1 {one minute ago}
  other {{{minutes}} minutes ago by {gender, select, male {male} female {female} other {other}}}}
</span>

Example 2: i18n angular

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      ng xi18n  --format=xlf
ng xi18n  --format=xlf2
ng xi18n  --format=xmb