Error saving workspace
Do not use transactional annotation
Variable name uniqueness check
Code clean
Fixed new variable form initialization
Merge branch 'dev' of github.com:openforis/calc into dev

Conflicts:
	calc-core/src/main/java/org/openforis/calc/engine/WorkspaceService.java
	calc-webapp/src/main/webapp/step-edit.html
Merge branch 'dev' of github.com:openforis/calc into dev

Conflicts:
	calc-webapp/src/main/webapp/step-edit.html