Pulled some duplicated code out of control.c into

read_lines_until_blankline.

ioutil.h

@@ -10,6 +10,7 @@ int readloop(int filedes, void *buffer, size_t size);
 int sendfileloop(int out_fd, int in_fd, off64_t *offset, size_t count);
 int splice_via_pipe_loop(int fd_in, int fd_out, size_t len);
 int read_until_newline(int fd, char* buf, int bufsize);
+int read_lines_until_blankline(int fd, int max_line_length, char ***lines);
 int open_and_mmap(char* filename, int* out_fd, off64_t *out_size, void **out_map);
 
 #endif