GitIgnore Netbeans IDE and Direnv development files

[dellgreen]

Exclude Netbeans and Linux development files from being included in the repository
.envrc
nb-configuration.xml

[khmarbaise]

Can you make a PR of it I appreciate to integrate that...

[khmarbaise]

Can you squash your commits...and mentioned the issue in your commit message like:

Fixed #293 - GitIgnore Netbeans IDE and Direnv development files
Optional description

Makes it easier for me...