Add search as you type for outline map.

[trievis]

Is your feature request related to a problem? Please describe.
For big file with a lot of outline, it helps if there is searching with "search as you type" for quick navigation of source code.

Describe the solution you'd like
The outline map is reduced according the context of search box.
Highlight of matching phrases

Describe alternatives you've considered
A shortcut key for invoke search as you type is also ok.
A pop up outline like Ctrl+O in eclipse is ok.

Additional context
A pop up outline like Ctrl+O in eclipse is ok.

[Gerrnperl]

[v1.0.0] Now added a simple search function, you can enter "/" or "?" and "=" at the bottom of the outline to search (you can use the shortcut key <Alt-l> to focus)