sdist and install now work

next step is using a custom data dir, and falling back on the package
data dir. Also, fixing --version.

overviewer_core/src/main.c

@@ -0,0 +1,46 @@
+/* 
+ * This file is part of the Minecraft Overviewer.
+ *
+ * Minecraft Overviewer is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Minecraft Overviewer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with the Overviewer.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "overviewer.h"
+
+static PyMethodDef COverviewerMethods[] = {
+    {"alpha_over", alpha_over_wrap, METH_VARARGS,
+     "alpha over composite function"},
+    {"render_loop", chunk_render, METH_VARARGS,
+     "Renders stuffs"},
+    {"get_render_modes", get_render_modes, METH_VARARGS,
+     "returns available render modes"},
+    {"get_render_mode_info", get_render_mode_info, METH_VARARGS,
+     "returns info for a particular render mode"},
+    {NULL, NULL, 0, NULL}       /* Sentinel */
+};
+
+PyMODINIT_FUNC
+initc_overviewer(void)
+{
+    (void)Py_InitModule("c_overviewer", COverviewerMethods);
+    /* for numpy */
+    import_array();
+
+    /* initialize some required variables in iterage.c */
+    if (init_chunk_render()) {
+        fprintf(stderr, "failed to init_chunk_render\n");
+        exit(1); // TODO better way to indicate error?
+    }
+    
+    init_endian();
+}