raop: Move base64 implementation to a util file

Base64 implementation is now in a common file called raop_util.c.
Old Base64 files are removed but copyright is preserved.

Original patch by Martin Blanchard, patch splitted by
Hajime Fujita <crisp.fujita@nifty.com>.

src/modules/raop/raop_util.h

@@ -0,0 +1,33 @@
+#ifndef fooraoputilfoo
+#define fooraoputilfoo
+
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2008 Colin Guthrie
+  Copyright Kungliga Tekniska högskolan
+  Copyright 2013 Martin Blanchard
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2.1 of the License,
+  or (at your option) any later version.
+
+  PulseAudio 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 Lesser General Public License
+  along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+/***
+  This file was originally inspired by a file developed by
+  Kungliga Tekniska högskolan.
+***/
+
+int pa_raop_base64_encode(const void *data, int len, char **str);
+int pa_raop_base64_decode(const char *str, void *data);
+
+#endif