Issue #185:Changed the pattern checking for passwords to verify strin…

[harinee]

Closes Issue #185

• Refactored the regex code to add checks for any string preceding or succeeding the passphrases (password|passphrase|pwd|pword|pass)
• Added checks for new passphrases (secret|key) to the above list
• Reduced possible false positives for 'pw', since it is too short, by introducing a specific patter to look for
• Added tests for the above, including negative scenarios

Note: Have not considered that the following tests should pass, because adding this logic will not let talisman remain tech stack agnostic
setPassword("12345678") and setenv(password, "12345678")