Clean up newsfeed poster UI
See issue #1383 (closed)
(Note: Also made a couple additional minor adjustments outside of the poster component)
- Removed redundant tooltip text on hashtag action button
- Made paywall dropdown cursor pointer only in clickable space
- removed white background color that was overflowing out of text input
- changed Tokens to tokens in boost creator tooltip
- replaced notifications tooltip with element title
- made hashtag selector instructions text case consistent with other action buttons
- fix topbar notifications/usermenu icon misalignment on window resize
