Introduce angular router

[ashutoshc8101]

Overview

1. This PR fixes or fixes part of NA
2. This PR does the following: Introduce angular router and migrate about page to it.

Proposal Link

Essential Checklist

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Proof that changes are correct

lazy-loading-2021-07-07_20.04.29.mp4

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[oppiabot]

Hi @ashutoshc8101. Due to recent changes in the "develop" branch, this PR now has a merge conflict. Please follow this link if you need help resolving the conflict, so that the PR can be merged. Thanks!

[sagangwee]

@ashutoshc8101 LGTM for codeowners, thanks!

[oppiabot]

Unassigning @sagangwee since they have already approved the PR.

[oppiabot]

Hi @ashutoshc8101, this PR is ready to be merged. Please address any remaining comments prior to merging, and feel free to merge this PR once the CI checks pass and you're happy with it. Thanks!

[oppiabot]

Hi @ashutoshc8101. Due to recent changes in the "develop" branch, this PR now has a merge conflict. Please follow this link if you need help resolving the conflict, so that the PR can be merged. Thanks!

[oppiabot]

Hi @ashutoshc8101. Due to recent changes in the "develop" branch, this PR now has a merge conflict. Please follow this link if you need help resolving the conflict, so that the PR can be merged. Thanks!