Linux sandboxing and build support

[erikmav]

Regarding the Linux question from #28: We definitely know it's needed, but it's not the max priority for some time yet. It would be ideal to have parity across all three OSes but for internal teams that we support it has not bubbled up to the top of the ask list.

[986253417]

the file of the path of BuildXL-master\Shared\Scripts\bxl.cmd , it's content :" powershell -NoProfile -ExecutionPolicy RemoteSigned %~dp0\Bx1.ps1 '=#singlequote# , " cannot execute success. first i change the Bxl.ps1 to bxl.ps1. then it will thrown out : The string is missing the terminator: ' . + CategoryInfo : ParserError:<;=:> [], parentContainsErrorRecordException