[FEATURE REQUEST] Support for dotnet new teamplates

[licon4812]

Please confirm these before moving forward.

• I have searched for my feature proposal and have not found a work-in-progress/duplicate/resolved/discarded issue.
• This proposal is a completely new feature. If you want to suggest an improvement or an enhancement, please use this template.

Describe the new feature

The dotnet SDK allows users to install and update templates. However, updates aren't automatic and require the user to constantly remember to do them.

Example command to check for updates --check-only

Output

Helpful commands

• dotnet new list : lists all the installed templates
• dotnet new update --check-only : checks templates that can be updated
• dotnet new update: updates all templates
• dotnet new install <package>::<version> installs/updates specific package
• dotnet new search <package> To search for templates, specify partial template name or use one of the supported filters: '--author', '--baseline', '--language', '--type', '--tag', '--package'.

Describe how this new feature could help users

This feature will allow users to update the dotnet new templates without having to constantly check manually. Due to UniGet providing notifications anyway