1diff --git b/LICENSE a/LICENSE
2new file mode 100644
3index 0000000..21f30fa
4--- /dev/null
5+++ a/LICENSE
6@@ -0,0 +1,19 @@
7+Copyright (c) 2019 Stepan Koltsov
8+
9+Permission is hereby granted, free of charge, to any person obtaining a copy
10+of this software and associated documentation files (the "Software"), to deal
11+in the Software without restriction, including without limitation the rights
12+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13+copies of the Software, and to permit persons to whom the Software is
14+furnished to do so, subject to the following conditions:
15+
16+The above copyright notice and this permission notice shall be included in all
17+copies or substantial portions of the Software.
18+
19+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
22+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
23+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24+OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
25+OR OTHER DEALINGS IN THE SOFTWARE.
26