RemoteFile: handle the slave unreachable case in FindFile()
Move mythlibdvdnav to externals.
Try to fix MSVC build after moving libmythdvdnav in [2e2e4b0].
let Smolt search for the langauge as global and local setting

Language became a global setting in [bf6fc7cd39].
let Smolt search for the country as global and local setting

Country became a global setting in [bf6fc7cd39]. This allows me to upload my
profile instead of getting error 500 from the server. It might be just
correlation though.
MythMusic: add a hostname column to the music_albumart table

Use the master BE's hostname as the initial value since this will be correct
for 99.9% of users. It's only used as a hint to where to find the file so even
if it is incorrect it will get corrected.
MythMusic: add support to the file scanner for music stored on slave BE's

This updates the file scanner so it can be run on both the master and slave
BE's adding any music/albumart it finds in the 'Music' storage group to the
database.
MainServer: update the SCAN_MUSIC command to also scan slave BE's

This forwards any SCAN_MUSIC commands sent to the master BE to any slaves that
have a directory defined in the 'Music' storage group.
Merge remote-tracking branch 'upstream/master'