[ACS-7429] cleanup APS1 task-list before refactorings

[DenysVuika]

Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x")

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation
• Other... Please describe:

What is the current behaviour? (You can also link to an open issue here)

ACS-7429

What is the new behaviour?

• lint: add missing docs in a few places
• remove unused View/Content child imports and HTML references
• cleanup the unused api in demo shell
• overall code cleanup
• remove old tslint
• remove unused image assets from demo shell

Does this PR introduce a breaking change? (check one with "x")

• Yes
• No

If this PR contains a breaking change, please describe the impact and migration path for existing applications: ...

Other information:

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
1.6% Duplication on New Code

See analysis details on SonarCloud