JC-1869 Simplified the test on QnA permission uniqueness
#JC-1869: Added possibility to override default create topic button

 In topic plugin configuration added property "order". Buttons in create topic dropdown will be sorted by this property. If this property is same buttons will be sorted by text.
 Note: create topic button have order value 100, create code rewiew button - 101
#JC-1869: Added more description about "magic" numbers (100 and 101)
#JC-1869: Added possibility to get information about current user inside of plugins
#JC-1869: Fixed remarks on github
Fixed a test that was failing from time to time.

Tests shouldn't depend on time otherwise there always be cases when it
ticks faster or slower than what tests think it will.
JC-1869 Fixed some javadocs, formatting, names, modifiers
#JC-1869: Corrected tooltips
#JC-1869: Fixed remarks
 *Now ReadOnlySecurityService Returns Anonymous user instead of null when user not logged in
*JCUser.copyUser method now performs deeper coping
 *Added unit tests
 *CreateTopicBtnDtoComparator now compares objects with same order value by id
#JC-1869: Plugin property explanation moved to tooltip
*Added new column HINT into PLUGIN_PROPERTY table. Now tooltip text stores in this column
*Added possibility view tooltip on span element when it hovered
#JC-1869 Fixed messages and done some refactoring
#JC-1869: Fixed remarks:
*labels names lowercased
*PluginController#getModel refactored
*Added unit tests for QuestionsAndAnswersPlugin
Merge branch 'master' of github.com:jtalks-org/jcommune

Conflicts:
	jcommune-plugins/questions-n-answers-plugin/src/main/java/org/jtalks/jcommune/plugin/questionsandanswers/QuestionsAndAnswersPlugin.java
#JC-1869:Merge conflicts resolution
Merge branch 'JC-1869_QuestionsPermissions'

Conflicts:
	jcommune-plugins/questions-n-answers-plugin/src/main/java/org/jtalks/jcommune/plugin/questionsandanswers/QuestionsAndAnswersPlugin.java
#JC-1869:Fixed error 500 with Kaptcha plugin configuration
#JC-1869:Unit tests for REadOnlySecurityService
#JC-1869:Unit tests for StatefullPlugin
#JC-1869:Added licence header
JC-1942 add condition to show empty section in admin mode