50% / max buttons for input fields

[kyleleow]

What kind of PR is this?:

/kind feature

What this PR does / why we need it:

• Add functionality to quickly set 50% of the balance in input field

Which issue(s) does this PR fixes?:

Fixes #375

[codeclimate]

Code Climate has analyzed commit 53284d9 and detected 0 issues on this pull request.

View more on Code Climate.

[netlify]

✔️ Deploy Preview for defi-wallet ready!

🔨 Explore the source changes: 53284d9

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😎 Browse the preview: https://deploy-preview-396--defi-wallet.netlify.app

[codecov]

Codecov Report

Merging #396 (53284d9) into main (b915adb) will increase coverage by 0.13%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #396      +/-   ##
==========================================
+ Coverage   87.00%   87.13%   +0.13%     
==========================================
  Files          93       94       +1     
  Lines        1400     1399       -1     
  Branches      208      210       +2     
==========================================
+ Hits         1218     1219       +1     
+ Misses        181      179       -2     
  Partials        1        1              

Impacted Files	Coverage Δ
app/components/SetAmountButton.tsx	100.00% <100.00%> (ø)
...ns/AppNavigator/screens/Balances/ConvertScreen.tsx	95.71% <100.00%> (-0.29%)	⬇️
...pNavigator/screens/Balances/screens/SendScreen.tsx	90.74% <100.00%> (-0.17%)	⬇️
...reens/AppNavigator/screens/Dex/DexAddLiquidity.tsx	98.48% <100.00%> (+2.96%)	⬆️
...pNavigator/screens/Dex/PoolSwap/PoolSwapScreen.tsx	94.11% <100.00%> (ø)

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[defichain-bot]

Build preview for DeFi Wallet is ready!

Built with commit f4a4074

https://expo.io/@defichain/wallet?release-channel=pr-preview-396

[cypress]

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Test summary

125 • 0 • 0 • 0

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Run details

Project	wallet
Status	Passed
Commit	f4a4074 ℹ️
Started	Aug 3, 2021 4:23 AM
Ended	Aug 3, 2021 4:36 AM
Duration	12:35 💡
OS	Linux Ubuntu - 20.04
Browser	Chrome 92

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