add libav 0.29+ to deps

CMakeLists.txt

@@ -4,7 +4,7 @@ project(notcurses VERSION 0.0.1
   HOMEPAGE_URL "https://nick-black.com/dankwiki/index.php/notcurses"
   LANGUAGES C CXX)
 set(CMAKE_C_STANDARD 11)
-set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD 14)
 
 configure_file(tools/version.h.in include/version.h)
 

README.md

@@ -66,6 +66,13 @@ On the other hand, if you're targeting industrial or critical applications,
 or wish to benefit from the time-tested reliability and portability of Curses,
 you should by all means use that fine library.
 
+## Requirements
+
+* A C11 and a C++14 compiler
+* CMake 3.13.0+
+* NCurses 6.1+
+* LibAV 0.29+
+
 ## Basic use
 
 A program wishing to use notcurses will need to link it, ideally using the