Upgraded pkgmgr

[anujdatar]

Added some logic in the install dependencies (package-management) part, to improve code readability/reusability, and make it easier to add support for more distros if necessary.

[anujdatar]

I was planning to add some support for other applications as well. And that would mean adding user input and some logic to the install file. I thought this just improves the code readability a bit, helps separate different parts of the script a bit better. Let me know what you think.

[harry-cpp]

I see what you are going for here, but it just makes it way harder to both read and maintain. Sometimes code just needs to be simple.

This kinda reminds me of: https://medium.com/@webseanhickey/the-evolution-of-a-software-engineer-db854689243