Fixing issue and improved network performance and added loader etc..

[rjoydip-zz]

This PR contains below points.

Description

• fix(warning): Can't perform a React state update on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all subscriptions and asynchronous tasks in a useEffect cleanup function
• fix(styled-component): To resolve this only create new Styled Components outside of any render method and function component
• improved(rendering): Very slow network rendering (Very slow network rendering almende/vis#3187)
• fix(state/travel): Error: Array index '-1' has to be an integer
• fix(travel:filter): TypeError: Cannot read property 'forEach' of undefined
• feat: loader functionality added
• network cluster performance improved
• memory leaking issues fixed some of the cases

Note: Loader designer is very much basic. Fell free to improve loader design after merged the PR.

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[sibeshkar]

Thanks for the fixes. the extra squigliness in the edges seems to be destroying any performance optimization you made. Possible to fix? Also needs a better loader, that can be located at the top left. Thanks :)

[rjoydip-zz]

@sibeshkar

the extra squigliness in the edges seems to be destroying any performance optimization you made
Fixed. But changed all png logos to svg for better rendering. Also changed others logo

• Images are taken from flaticon
• Changed those gradient colored images (if required)
• Loader placed on left top but the not responsive

Note: For further performance improvement and better resource loading you have to merge #171 PR