Some new methods added

Campaigns (+content & actions), create lists, merge-fields, email-activity & unsubscribed, thanks to @REDGML

An issue with processing errors fixed

An issue with processing errors fixed. Thanks to @aqman1 .

Issue #3 resolved

Issue #3 resolved, thanks to @IVIyg0t

Some lists methods added

Some lists methods added, thanks to @apocheau

3.0-0.9.2

Initial commit