Bisamware ransomware removal [.Bisamware file virus].

Brief quotation from the ransom note is below:
QUOTE
RANSOMWARE NOTE
YOUR SYSTEM GOT INFECTED WITH A RANSOMWARE
CONTACT US DOWN BELOW AT OUR TOR ONION LIVE CHAT SYSTEM FOR DECRYPTION HELP
IF YOU "DONT" WANT THE FILES BACK - RESET YOUR PC
100% DECRYPTION AFTER PURCHASE OF DECRYPTION KEY - ONLY WE HAVE IT IN OUR DATABASE
YOU CAN CALL THE COPS - YOU CAN CALL ANY MASTER TECHNICAL SOFTWARE DEVELOPER BUT IT WONT HELP
WE ARE SPECIALIZED TO TARGET COMPANIES - THERE IS NO WAY TO RECOVER YOUR FILES WITHOUT GETTING THE DECRYPTION KEY
UNQUOTE