Nickname Search Mode

[firejox]

This idea is borrowed from the web browser Vivaldi. It allows user type different nickname to switch different search engine. For example,

• g [search pattern] will search with Google Search
• w [search pattern] will search with Wikipedia.

In CtrlP, it can be:

• f [search pattern] will search file
• b [search pattern] will search buffer
• t [search pattern] will search tag
  and so on.

I think this will be great because people don't need to keep pressing <c-f>/<c-b> to switch mode and then search.