check for and build with SDL2

wscript

@@ -8,6 +8,7 @@ def options(opt):
 def configure(conf):
     conf.load("compiler_c compiler_cxx")
     conf.check(header_name = "getopt.h")
+    conf.check_cfg(package = "sdl2", args = "--cflags --libs")
 
 def build(bld):
     includes = [p for p in bld.path.ant_glob("src/**", dir = True) if os.path.isdir(p.abspath())]
@@ -18,7 +19,8 @@ def build(bld):
         includes = includes,
         defines = ['GLCXX_GL_INCLUDE="gl3w.h"'],
         cxxflags = ["-Wall", "-std=gnu++14"],
-        lib = ["dl", "GL"])
+        lib = ["dl", "GL"],
+        uselib = "SDL2")
 
     test_libs = []
     if re.search(r'linux', platform.platform(), re.IGNORECASE):