Clear warnings from deprecated functionality in numpy 1.7

Refs #9421
Clear gcc 4.8 warning about non-trivial move assignment operator

C++11 dictates that move assignment operators will only be auto-generated
when a set of circumstances is met. One of these is the lack of a
user-defined destructor. Add virtual destructors to the Fit hierarchy
avoids the compiler generating trivial move-assignment ops and avoids
the warning in virtually inheriting subclasses, e.g Python
IPeakFunctionAdapter.cpp.
Refs #9421
Suppress gcc 4.8 warnings on gtest 1.7 code.

Refs #9421
Fix gcc 4.8 warnings in ICat.

Refs #9421
Fix gcc 4.8 warnings from API

Refs #9421
Fix warnings about use of unitialized variabies in MantidNexus

Refs #9421
Kill gcc 4.8 warnings in tests.

Refs #9421
Fix numpy array writable flag setter.

Refs #9421
Merge branch 'bugfix/9421_gcc4.8_numpy1.7_warnings' into develop

Conflicts:
	Code/Mantid/Framework/DataObjects/test/ManagedWorkspace2DTest.h
Refs #9421