Rename sqlite3.{c,h} to sqlite3-binding.{c,h}

This fixes the problem where when building with gccgo, sqlite3.c is
overwritten, leading to a build failure.

An alternative would have been to move sqlite3*.{c,h} to a subdirectory,
but that seems to confuse the linker a fair bit and would just swap one
implementation-dependent issue for another.

Closes #20

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>

sqlite3.go

@@ -9,7 +9,7 @@ package sqlite3
 #cgo CFLAGS: -std=gnu99
 #cgo CFLAGS: -DSQLITE_ENABLE_RTREE -DSQLITE_THREADSAFE
 #cgo CFLAGS: -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_PARENTHESIS
-#include <sqlite3.h>
+#include <sqlite3-binding.h>
 #include <stdlib.h>
 #include <string.h>