feat(auto_install): Switch from nvim-lsp-installer to mason.nvim + various other improvements.

[connorgmeehan]

Big changes:

• This PR switches from nvim-lsp-installer -> mason.nvim.
• Adds a standardised set of options to modify and configure the null-ls/lsp sources of modules without overriding it.
• Fixed and improved formatting of the logging service.
• Added a new element to the statusline that indicates when a package is being installed. This element can be clicked to bring up the :Mason menu.
  • 
• Seperates the config language module into json, yaml, toml modules.
• Tested and fixed all language startup issues to the best of my ability.

Extra minor changes to statusline:

• Made statusline always show filetype.
• Split LSP indicator into it's own statusline element + made it clickable.

Most of the extra LOC are boilerplate to allow users to configure the LSP/Null-ls sources.