Fixes #155 : Fixed the delay while moving up the top bar

[kavithaenair]

Short description

Fixes #155
Related to issue #77 and PR #142

Changes:
Demo link : https://kavithaenair.github.io/

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[kavithaenair]

@djmgit @daminisatya open for review

[djmgit]

This speeds up the hiding animation no doubt although delay is still there.However it looks good to me.
@mariobehling Just a doubt.I guess the original issue which brought in this change is this #77 The desired effect was that of google play store which we do not have yet.Presently apps.loklak.org has got a different scrolling effect which is different from that of playstore. So should we make this effect final or is issue #77 still valid?

[mariobehling]

@djmgit I think it is good enough for now and we can come back to this later, if we want it even closer to Google.