add: day wise log split and log files management

[mratanusarkar]

Improvisation of the existing implementation. This will enable the logs to be split day-wise and also manage the files and have some sort of retention policy or auto-delete after a certain number of days.

This fixes issue: #2

Topic Breakdown:

• fix the issue of logs not getting split into date-wise logs
• implement log management (so that the log files don't overflow taking up memory)
• implement an auto-delete or auto-archival of the logs
• implement a retention policy

TODO (for future reference):

• make the implementation values dynamic and configurable (remove hardcoded values)
• make the existing metadata dynamic and configurable (remove hardcoded values)

[mratanusarkar]

• tried modifying new Date() placement in logger.js to see if the files get split.
• tried deleting log files or the log text content inside the log files to see if the files get recreated with a new date.
• realized that this doesn't work because of how Winston is created. The config file is called one time at the beginning of the application start, and it's like an object.
• searched through GitHub issues and forums to tackle this type of requirement.

[mratanusarkar]

I found the following GitHub issues relevant to this problem:

• Winston issue#10: Add ability for File transport to split up logs by date winstonjs/winston#10
• Winston PR#205: added dailyRotateFile transport. winstonjs/winston#205

It seems like we have to rely on another package by the Winston foundation:
winston-daily-rotate-file

Implementation of the above package would take care of the following requirement:

1. split log files according to date, time, or memory size.
2. delete older log files (say 30 days or 60 days old files)

[mratanusarkar]

• implemented winston-daily-rotate-file
• tried out various configurations for "log file rotate", "split logs datewise" and "auto deletion of old logs"
• working on playing with config and testing the outcome and behavior matches with the expectation

Note: we can also set the log rotation frequency to anything else and not necessarily daily.
This should be a good generalization point for future TODOs.

[mratanusarkar]

merging PR as v1.0.1