add new theme named Jijeesh

[jijeesh]

Standards checklist:

• The PR title is descriptive.
• The PR doesn't replicate another PR which is already open.
• I have read the contribution guide and followed all the instructions.
• The code follows the code style guide detailed in the wiki.
• The code is mine or it's from somewhere with an MIT-compatible license.
• The code is efficient, to the best of my ability, and does not waste computer resources.
• The code is stable and I have tested it myself, to the best of my abilities.
• If the code introduces new aliases, I provide a valid use case for all plugin users down below.

Changes:

• [...] I have added new theme
• screen shot is given below
  

Other comments:

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[jijeesh]

[carlosala]

We can't accept more themes. Please make a separate repo with your theme and link to it from the external themes wiki page.

You can also add your theme as a custom theme. See customization for instructions.