Add .clang_format

Also applies clang-format to the current code base, using command:
`find . -regex '.*\.\(c\|h\)' -exec clang-format -style=file -i {} \;`

overviewer_core/src/main.c

@@ -17,7 +17,7 @@
 
 #include "overviewer.h"
 
-PyObject *get_extension_version(PyObject *self, PyObject *args) {
+PyObject* get_extension_version(PyObject* self, PyObject* args) {
 
     return Py_BuildValue("i", OVERVIEWER_EXTENSION_VERSION);
 }
@@ -25,31 +25,28 @@ PyObject *get_extension_version(PyObject *self, PyObject *args) {
 static PyMethodDef COverviewerMethods[] = {
     {"alpha_over", alpha_over_wrap, METH_VARARGS,
      "alpha over composite function"},
-    
+
     {"resize_half", resize_half_wrap, METH_VARARGS,
      "downscale image to half size"},
-    
+
     {"render_loop", chunk_render, METH_VARARGS,
      "Renders stuffs"},
-    
-    {"extension_version", get_extension_version, METH_VARARGS, 
-        "Returns the extension version"},
-    
-    {NULL, NULL, 0, NULL}       /* Sentinel */
+
+    {"extension_version", get_extension_version, METH_VARARGS,
+     "Returns the extension version"},
+
+    {NULL, NULL, 0, NULL} /* Sentinel */
 };
 
 static PyModuleDef COverviewerModule = {
     PyModuleDef_HEAD_INIT,
     "c_overviewer",
-    "",     // TODO: Add documentation here.
+    "", // TODO: Add documentation here.
     -1,
-    COverviewerMethods
-};
-
+    COverviewerMethods};
 
 PyMODINIT_FUNC
-PyInit_c_overviewer(void)
-{
+PyInit_c_overviewer(void) {
     PyObject *mod, *numpy;
     mod = PyModule_Create(&COverviewerModule);