INSTALL file is outdated

[Yevhenii Mamontov <yevheniy.mamontov@xxxxxxxxx>]

Hello, dear team.
I've faced with a problem of building your lib on Windows.
Your INSTALL file does not contain proper steps - only "use vcpkg &
cmake-gui.exe".
You didn't mentioned about how to link installed vcpkg packages, your list
of mandatory libs for build is not full (zlib you use even though you said
it is optional).

Please, provide normal build guide in order to everyone could use your work.
Thanks in advance.
-- 
Sincerely, Yevheniy Mamontov.