build: make bootstrap script fail properly on failure

If the first command in the bootstrap script fails, exit with non-zero
exit status instead of silently continuing to the next command.
check mime type of internet streams. allows hls playlists without m3u8 extension to be played
FIX: do not popup OSD on DVD menu with touch or mouse
[addons] switch general.addonupdates to an integer setting. Skins can use a button control for the setting instead of a
toggle.
[addons] adds 'never' as an option for the addon update setting
[confluence] use a button for the addon update setting to allow for 'never' as an option
[addons] change root of add-on manager to unsorted rather than sort by label
[addons] adds LastRepoUpdate() to the add-on installer
[addons] adds 'Check for updates' to the root of the add-ons manager.
[addons] show all add-ons in the add-on manager, including libraries/modules/helpers
FIX: [droid] enable compilation with NDK >= 9b
Startup log: fix POSIX/LINUX, better report FFMpeg, cosmetics
Startup log: Split long log string, add special version build information
[win32] SysInfo: implement and use sysGetVersionExWByRef() to overcome Win8.1 limitation on getting real Windows version
SysInfo: add GetKernelName() function for all platforms
SysInfo: rename GetKernelVersion -> GetOsNameWithVersionInfo
SysInfo: add GetKernelVersionFull() and GetKernelVersion() functions for all platforms
[omxplayer] Avoid hang when closing stream with clock stopped

Avoids a permanent hang at EOF when using IPTV streams
[linux] SystemInfo.cpp: add local static helpers getValueFromOs_release() and getValueFromLsb_release()
SysInfo: add GetOsName() function for all platforms