add support for linux build

sdl/01-sdl2-init/build.gradle

@@ -9,7 +9,7 @@ sources {
                 include "**/*.c"
             }
             exportedHeaders {
-                srcDir "../build/SDL2-2.0.3/include"
+                srcDir "../build/include"
             }
         }
     }
@@ -20,7 +20,9 @@ executables {
         binaries.all {
             if (toolChain in VisualCpp) {
                 cCompiler.args "/MD"
-                linker.args "/SUBSYSTEM:CONSOLE", "/LIBPATH:../build/SDL2-2.0.3/lib/x86/", "SDL2main.lib", "SDL2.lib"
+                linker.args "/SUBSYSTEM:CONSOLE", "/LIBPATH:../build/lib/", "SDL2main.lib", "SDL2.lib"
+            } else if (toolChain in Gcc) {
+                linker.args "-lSDL2"
             }
         }
     }

sdl/01-sdl2-init/src/main/c/sdl-init.c

@@ -1,6 +1,6 @@
 // SDL2 example - initialize and quit
 
-#include "SDL.h"
+#include "SDL2/SDL.h"
 
 int main(int argc, char** argv){
     SDL_Init(SDL_INIT_EVERYTHING);