TEXroot: Allow path expansion

[sinus-x]

LaTeXtools does not recognise ~ as path alias and (probably) treats it as just a character. Because of that, full path is neccesary:

"settings": {
  "TEXroot": "/home/user/Projects/project/main.tex"
}

Would it be possible to do just

"settings": {
  "TEXroot": "~/Projects/project/main.tex"
}