Merge .deb postinst and postinst.oss

Merge pull request microsoft#4744 from Microsoft/ben/fix-4739

New untitiled file not saved on exit (fixes microsoft#4739)

Fix deb postinst script

Fixes microsoft#3894: findPrevBracketInToken reported incorrect range…

… for bracket match

Fixes microsoft#3894: findPrevBracketInToken reported incorrect range…

… for bracket match

Fixes microsoft#3594: copy over filenamePatterns when validating lang…

…uage extension point

workaround for json autocomplete does not escape \ in strings? micros…

…oft#3485

Bump version to 0.10.9 for january recovery release

jrieken.vscode-omnisharp > ms-vscode.omnisharp

bump version to 0.10.7 for january stable release