Proposing a fix for issues#16

[hussaintamboli]

I have been struggling with issues where excel converts big numbers to scientific format. e.g. 200420340204032403204 into 2.0042E+20. And it's really painful to convert it back to original textual format.

I need an option in ExcelResponse to control this behaviour.

[codecov]

Codecov Report

Merging #22 into master will increase coverage by 0.03%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #22      +/-   ##
==========================================
+ Coverage    96.7%   96.73%   +0.03%     
==========================================
  Files           1        1              
  Lines          91       92       +1     
  Branches       20       20              
==========================================
+ Hits           88       89       +1     
  Misses          1        1              
  Partials        2        2

Impacted Files	Coverage Δ
excel_response/response.py	96.73% <100%> (+0.03%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update b532d98...6f5d524. Read the comment docs.

[tarkatronic]

@hussaintamboli Thank you for your contribution; this does look like a good fix! Can you add a test just to verify the behavior with guess_types turned on and off? With that, it looks like it will be good to merge!

[tarkatronic]

Thank you! I will try to get a new version out ASAP with this fix.