addons manager leaks
The add-ons leaks left and right:
Indirect leak of 618 byte(s) in 103 object(s) allocated from:
[#0](https://code.videolan.org/videolan/vlc/-/issues/0) 0x7f49cffdef30 in strdup (/usr/lib/x86_64-linux-gnu/libasan.so.3+0x57f30)
[#1](https://code.videolan.org/videolan/vlc/-/issues/1) 0x7f4998d3b63e in ParseCategoriesInfo ../../modules/misc/addons/vorepository.c:265
[#2](https://code.videolan.org/videolan/vlc/-/issues/2) 0x7f4998d3c375 in Find ../../modules/misc/addons/vorepository.c:336
[#3](https://code.videolan.org/videolan/vlc/-/issues/3) 0x7f49cf421dd6 in FinderThread ../../src/misc/addons.c:355
[#4](https://code.videolan.org/videolan/vlc/-/issues/4) 0x7f49ce4e4493 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x7493)
(This also occurs before changes made May 14 2017.)