Fixed #674
Merge branch 'master' of github.com:qreal/qreal into fix674
Fixed slow element addition to scene
Merge branch 'fix674' of git://github.com/dvvrd/qreal
Merge pull request #767 from dvvrd/fix674

Fixed #674
Merge pull request #768 from dvvrd/fix676

Fixed #676
Version incremented to 2.3.1
Installing to C:\QRealRobots by default, warning about spaces and brackets.
Merge pull request #769 from dvvrd/robots231

QReal:Robots 2.3.1
Merge branch 'master' of https://github.com/qreal/qreal into installer
Merge pull request #770 from qreal/installer

Installer fixes
Merge branch 'robots' of github.com:dvvrd/qreal into robots

Conflicts:
	qrgui/umllib/nodeElement.cpp