Git commits in Moodle 3.1.x by Tim Lock

commit dfbbb39a25618a49974fa914a7678b68cfe5e738
Author: Tim Lock <tim@netspot.com.au>
Date:   Tue, 17 Jan 2017 09:50:26 +0800
Tag:    v3.1.5

MDL-57668 mod_assign: Fix optional_param() form processing


commit 42d6fc0b83c6414654a248f37295c80ce5b7e0ec
Author: Tim Lock <tim@netspot.com.au>
Date:   Mon, 28 Nov 2016 08:02:49 +0800
Tag:    v3.1.4

MDL-57170 repository_dropbox: Ensure Dropbox Legacy continues to work


commit fedb3cf539ac4cf0962e189646370dd39cfaafbe
Author: Tim Lock <tim@netspot.com.au>
Date:   Wed, 19 Oct 2016 09:41:14 +0800
Tag:    v3.1.3

MDL-56481 tool_lpmigrate: Fix notice when cancelling framework migration


commit 5e80e0bce91dfa1ec1d927f24971ab6bc593355a
Author: Tim Lock <tim@netspot.com.au>
Date:   Tue, 18 Oct 2016 10:19:47 +0800
Tag:    v3.1.3

MDL-55456 course: set context for category ajax requests


commit fe9831dd7d0c56b2ff931787cd47952985c53bf1
Author: Tim Lock <tim@netspot.com.au>
Date:   Tue, 18 Oct 2016 09:39:05 +0800
Tag:    v3.1.3

MDL-56466 assign: fix database error with team submissions