added UserPicker that allow you to pick users from a set of groups. You
can call this picker using

baseUrl/secure/popups/MailRuUserPickerAction.jspa?formName=jiraform&multiSelect=false&decorator=popup&element=customfield_12202&groupNames=jira-developers,test-group

add mailruuserpicker.jsp to /atlassian-jira/secure/popups  on your jira
server
Merge branch 'master' of https://github.com/DmitryMiroshnichenko/jira-mailru-plugins-utils

Conflicts:
	pom.xml