[language] add string locations
LangCodeExpander: add MKV language code
Merge pull request #3427 from Karlson2k/langcodexpander_fix_01

LangCodeExpander: add MKV stream code
Merge pull request #3121 from Karlson2k/timeout_fix_01

Fix incorrect (non wrap safe) timeout process
Merge pull request #3433 from Karlson2k/regexp_rework_01a

RegExp rework - part 01
[iOS] - for completeness add iPhone5c and iPhone5s models to our platform compatibility list
Merge pull request #3438 from MartijnKaijser/string_locations

[language] add string locations
Merge pull request #3435 from Karlson2k/regexp_rework_03

RegExp rework - part 03
RegExp: runtime check for UTF-8 support
RegExp: runtime check for Unicode properties support
Startup log: warn if PCRE built without UTF-8 support or without Unicode properties support
RegExp: use UTF-8 regexps (off by default)
RegExp: report UTF-8 specific errors
FileItemList: use UTF-8 regexps
CUtil: use UTF-8 regexps for CleanString and ExcludeFileOrFolder
ExternalPlayer::Process: use UTF-8 regexp
PlayerSelectionRule::GetPlayers: use UTF-8 regexp
StackDirectory: use UTF-8 regexp
VideoInfoScanner: use UTF-8 regexp
ScraperParser: use UTF-8 regexp