Enhancement: EstimateIsFeePaidEnough

[tigh-latte]

Calculate if fee's have been paid, base on an estimation of what the tx's signed inputs will be.

[codecov-commenter]

Codecov Report

Merging #44 (578c81f) into master (7a05422) will decrease coverage by 0.00%.
The diff coverage is 69.23%.

❗ Current head 578c81f differs from pull request most recent head e60a76f. Consider uploading reports for the commit e60a76f to get more accurate results

@@            Coverage Diff             @@
##           master      #44      +/-   ##
==========================================
- Coverage   86.05%   86.04%   -0.01%     
==========================================
  Files          26       26              
  Lines        2804     2817      +13     
==========================================
+ Hits         2413     2424      +11     
- Misses        269      270       +1     
- Partials      122      123       +1     

Impacted Files	Coverage Δ
tx.go	79.41% <69.23%> (+0.35%)	⬆️

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[jadwahab]

@Tigh-Gherr what is this function for? like who would use it and where?

[theflyingcodr]

LGTM

[tigh-latte]

@jadwahab if a user of go-bt would like to see if their tx has enough inputs to cover fees + change before signing, to save signing, checking, adding, and re-signing.