Feature/connect as sysdba

[pesse]

• Adds some Unit-Tests around parsing connectString
• Allows user-part of the connectstring to contain "/" if enclosed in double quotes (e.g. "my/user"/pass@connectstring)
• Allows password-part of the connectstring to contain "@" if enclosed in double quotes (e.g. app/"myP@ssw/rd="@connecstring)
• Allows to connect as sysdba via adding the "as" part to the username (e.g. "sys as sysdba"/pass@connectstring) (Fixesas sysdba #115)