Merge branch 'hotfix/0.2.2'
Merge branch 'master' into develop
moved the tag validator to helpers
removed the constructor and init() from the persister interface
introdcued an abstract persister class
using the abstract persister class in changelog persister
semantic generator does not provide the regex anymore
using the abstract persister class in vcs  persister
refactored the composer config helper. can be used to read and write the version
persister for composer files
code cleanup
code cleanup
new exception type
removed "vcs-tag" option from current command
catching the noconfiguration exception
code cleanup
changed version persister to composer
display last changes task does not use method unknown to interface anymore
semantic version generator does not need context anymore
composer can be configured as version-persister