Implement file read function

[andrewdavidmackenzie]

Fixes #1719

[codecov]

Codecov Report

Merging #1764 (611e64c) into master (28b44b2) will increase coverage by 0%.
The diff coverage is 93%.

@@          Coverage Diff           @@
##           master   #1764   +/-   ##
======================================
  Coverage      90%     90%           
======================================
  Files         106     107    +1     
  Lines       16144   16191   +47     
======================================
+ Hits        14539   14584   +45     
- Misses       1605    1607    +2     

Impacted Files	Coverage Δ
flowr/src/cli/coordinator_message.rs	28% <ø> (ø)
flowr/src/cli/cli_client.rs	85% <50%> (ø)
flowr/src/cli/file/file_read.rs	95% <95%> (ø)
flowr/src/cli/mod.rs	100% <100%> (ø)