enable shared lib support in linux for lua

gyp/tools.gyp

Index: gyp/tools.gyp
diff --git a/gyp/tools.gyp b/gyp/tools.gyp
index d960cdc1289b97e2227fb27053aabbf4a3f87d7f..c7de7632d419388ff8a88b445abbf2969c56beb8 100644
--- a/gyp/tools.gyp
+++ b/gyp/tools.gyp
@@ -98,6 +98,25 @@
       ],
     },
     {
+      'target_name': 'sklua',
+      'type': 'shared_library',
+      'sources': [
+        '../src/utils/SkLuaCanvas.cpp',
+        '../src/utils/SkLua.cpp',
+      ],
+      'include_dirs': [
+        '../third_party/lua/src/',
+      ],
+      'dependencies': [
+        'lua.gyp:lua',
+        'pdf.gyp:pdf',
+        'skia_lib.gyp:skia_lib',
+      ],
+      'ldflags': [
+        '-Wl,-rpath', '-Wl,./',

[bungeman-skia, 2013/06/18 20:28:06]

is it possible to just use '-Wl,-rpath=./' to avoid splitting the flag? Also,
this seems ld specific, perhaps this should go in a conditional to not add this
on Windows (not sure if this is used on Windows anyway)?

+      ],
+    },
+    {
       'target_name': 'lua_app',
       'type': 'executable',
       'sources': [