Git commits in Moodle 3.0.5 by Mark Nelson

commit fcebfea419a2be48a0203f673fd604e609ecbab7
Author: Mark Nelson <markn@moodle.com>
Date:   Tue, 17 May 2016 13:43:12 +0800
Tag:    v3.0.5

MDL-52599 block_rss_client: fixed various PHP errors


commit 86f523fdf972e8020e0684e839f3345a849910be
Author: Mark Nelson <markn@moodle.com>
Date:   Thu, 12 May 2016 14:28:44 +0800
Tag:    v3.0.5

MDL-54101 core: fixed core/str get_string caching issue


commit ac6d4ce7281219d4553df34a8da44b5d6b700dc4
Author: Mark Nelson <markn@moodle.com>
Date:   Tue, 10 May 2016 17:09:37 +0800
Tag:    v3.0.5

MDL-54125 mod_data: fixed PHP notice