add `sourceIndex` to `Selector` nodes#290

alexander-akait merged 2 commits intopostcss:masterpostcss/postcss-selector-parser:masterfrom

romainmenke:add-source-index-to-selector-nodes--courteous-echidna-efbdb3ba14romainmenke/postcss-selector-parser:add-source-index-to-selector-nodes--courteous-echidna-efbdb3ba14Copy head branch name to clipboard