Dont work vkn command

Add in bir/vkn

``` bash
#!/usr/bin/env bash

PROJECT_DIR=$1

if [[ -z ${PROJECT_DIR} ]]; then
    echo ERROR. PARAMETER PROJECT DIRECTORY IS EMPTY
    exit 1
fi

DIRNAME=$(dirname $0);
LINK=`readlink "$0"`

if [ -n "$LINK" ]; then
    ABSOLUTE_DIRNAME=$(dirname ${DIRNAME}/${LINK}/)
else
    ABSOLUTE_DIRNAME=${DIRNAME}
fi

CURRENT_DIR=$(pwd)
(cd ${ABSOLUTE_DIRNAME} && npm start)
```
