Merge remote-tracking branch 'origin/master' into vlan/cond-resolve

diff --cc python/educational-python/course-creator-python/src/com/jetbrains/edu/coursecreator/PyCCReferenceResolveProvider.java
Simple merge

diff --cc python/educational-python/src/com/jetbrains/python/edu/PyEduUtils.java
Simple merge

diff --cc python/educational-python/student-python/src/com/jetbrains/edu/learning/PyStudyReferenceResolveProvider.java
Simple merge

diff --cc python/src/com/jetbrains/python/psi/impl/PyClassImpl.java
Simple merge

diff --cc python/src/com/jetbrains/python/psi/types/PyClassTypeImpl.java
Simple merge

diff --cc python/src/com/jetbrains/python/refactoring/introduce/field/PyIntroduceFieldHandler.java
Simple merge