Merge pull request #26 from php-workx/extended_recurrence_rules

extended rrules to make them more flexible and solve #24
Merge pull request #27 from php-workx/extended_timezone_support

Extended timezone support
Ignore composer.lock
Add Several Attendees (Fixes #18)

This commit contains a small refactor so that a Property can return multiple lines instead of only a single line, and Component now asks for all lines of a property.  This is important, as some properties such as Attendee can be declared multiple times.
Moved colon escaping to proper location and added a test
Merge pull request #28 from navarr/several-attendees

Add Several Attendees
Fixed some documentation, dependencies and travis CI
Fixed .scrutinizer.yml configuration and README badges
additional calendar properties to improve compatibility