Add file_size() function to FileIOMessageWriter

[zariiii9003]

Close #1359

[codecov]

Codecov Report

Merging #1367 (84d691c) into develop (73663b6) will increase coverage by 0.00%.
The diff coverage is 75.00%.

@@           Coverage Diff            @@
##           develop    #1367   +/-   ##
========================================
  Coverage    66.13%   66.13%           
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  Files           86       86           
  Lines         8998     9004    +6     
========================================
+ Hits          5951     5955    +4     
- Misses        3047     3049    +2     

[j-c-cook]

It appears that you plan to close #1359 with this PR. Do you plan to merge this and close #1360 without a merge? If so, there are changes in #1360 that are not included here, but should be to properly close #1359. I have created a pull request into your branch: zariiii9003#5. These additions will currently accomplish the following two items:

• Modify help statement for -s to indicate blf behaves differently j-c-cook@f7e4845
• Open max_container_size in blf writer to API via kwargs j-c-cook@77c8685

One additional item that I have not yet had time to address is based on @hardbyte's comment:

• Fix the sized rotating logger size bug for the blf writer #1360 (comment)

[zariiii9003]

I merged your changes. Once #1366 is merged, you can pass any parameters from the CLI to the logger instantiation.