Add Theme: Oceanic-Next

[R055A]

Description

Add a new theme: oceanic-next

Sourced from: https://github.com/mhartington/oceanic-next

#32

Type of change

• New feature (added a non-breaking change which adds functionality)
• Updated documentation (updated the readme, templates, or other repo files)

How Has This Been Tested?

• Tested locally with a valid username
• Tested locally with an invalid username
• Ran tests with composer test

Checklist:

• I have checked to make sure no other pull requests are open for this issue
• The code is properly formatted and is consistent with the existing code style
• I have made corresponding changes to the documentation
• My changes generate no new warnings

Screenshots

[Yogesh-rana-2301]

You should update the themes.md file also, and add oceanic-Next theme in it accordingly.

[R055A]

You should update the themes.md file also, and add oceanic-Next theme in it accordingly.

@DenverCoder1 spam?