ADD: Support to view text files

[Neelesh2512]

Problem
Currently if s3 files does not have any extension or extension like .log, commuter only gives open to download the files.

Suggestion
Extend extension support to view files

Note
I have implemented and tested changes locally and happy to contribute to repo. Attaching screenshot below. Which is a log file generated by spark without any extension. I am storing it in s3 and using commuter to view files.