Added Version class representing editor version
Added test for Version class in qrkernel
Added more tests for version class
Merge branch 'master' of github.com:qreal/qreal into metamodels
Repository extended with meta-information.
Added test case for meta-information in repo component
Metamodels extended with their version;
Meta-information repository API made accepting QVariant type.
Added metamodel version storing into save.
Added some save file verification steps before opening;
Disabled pasting of unknown elements.
Styleguide fixes
Merge pull request #1257 from dvvrd/metamodels

Save file verification & editor versions