Update README.md

Update README.md

add passphrase and key resource close

Update README.md

add test for rsa

Merge branch 'issue-5-wrong-condition-for-exp'

Merge pull request #6 from miladrahimi/issue-5-wrong-condition-for-exp

fix greater/less than validators

merge

Merge pull request #4 from miladrahimi/dev

fix security issue

Merge pull request #3 from miladrahimi/dev

Dev