switch from MIT license to ISC license

https://opensource.org/licenses/ISC

LICENSE

@@ -0,0 +1,6 @@
+ISC License (ISC)
+Copyright 2018 Shinnosuke Watanabe
+
+Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

README.md

@@ -76,6 +76,4 @@ Document types that you can use to run stylelint against if you are using CSS in
 
 ## License
 
-Copyright (c) 2015 - 2018 [Shinnosuke Watanabe](https://github.com/shinnn)
-
-Licensed under [the MIT License](./LICENSE).
+[ISC License](./LICENSE) © 2018 Shinnosuke Watanabe

package.json

@@ -7,7 +7,7 @@
 	"repository": "https://github.com/shinnn/vscode-stylelint",
 	"homepage": "https://github.com/shinnn/vscode-stylelint#readme",
 	"bugs": "https://github.com/shinnn/vscode-stylelint/issues",
-	"license": "MIT",
+	"license": "ISC",
 	"icon": "media/icon.png",
 	"galleryBanner": {
 		"color": "#32CD32",