Update README.md

Author: RijulGulati

README.md

@@ -2,12 +2,12 @@
 CLI program to encrypt/decrypt [andOTP](https://github.com/andOTP/andOTP) files.
 
 ## Installation
-```
+```sh
 $ go get github.com/grijul/go-andotp
 ```
 
 ## Usage
-```
+```sh
 Usage: go-andotp -i <INPUT_FILE> {-e|-d} [-o <OUT_FILE>] [-p PASSWORD]
 
   -d    Decrypt file
@@ -22,19 +22,19 @@ Usage: go-andotp -i <INPUT_FILE> {-e|-d} [-o <OUT_FILE>] [-p PASSWORD]
 
 ## Examples
 - Encrypt JSON file (Password is asked after hitting ```Enter```. Password is not echoed)
-```
+```sh
 $ go-andotp -e -i file.json -o file.json.aes
 ```
 - Encrypt JSON file (Password is entered through CLI)
-```
+```sh
 $ go-andotp -e -i file.json -o file.json.aes -p testpass
 ```
 - Decrypt JSON file
-```
+```sh
 $ go-andotp -d -i file.aes.json -o file.json
 ```
 - Decrypt JSON file and print json to console
-```
+```sh
 $ go-andotp -d -i file.aes.json
 ```