add project description and usage

Author: halyna-dev

README.md

@@ -1,2 +1,21 @@
 # niceDiff
-Get difference beetwine two branches or file into readeble HTML file.
+:star:**niceDiff**:star: helps to get the difference between two branches in a readable html file.
+![](niceDiff.gif)
+
+#### How to use
+1. Clone this repo
+    ```
+    git clone https://github.com/halyna-dev/niceDiff.git
+    ```
+2. Add niceDiff folder to your PATH variable. Don't forget reload your machine or logout/login from your windows account.
+3. Run niceDiff command from your git repo
+    ```
+    niceDiff <branch1-name> <branch2-name> [optional <path-to-comparing-files>]
+    ```
+4. Open file in the your folder with git repo
+    ```
+    niceDiff-report.html
+    ```
+
+#### How it works
+niceDiff is based on the standard git diff command. Magic is in batch parsing result. parseDiff.bat gets standard git diff output and tries to parse line by line.