One-line fix in build system for DESTDIR being set twice; once in the root
Makefile and then stacked in a second time by libspud's makefile, leading to
spurious doubled­up paths when 'make install-diamond' is run.
Lifted equation_type_index (shich makes expensive calls to spud) outside an element loop. Updated configure so that --enable-profiling is passed down into libspud so that excessive calls to spud can be more easily monitored.
1. Lifted equation_type_index (which makes expensive calls to spud) outside an element loop. This made the RANS test problem I was looking at run 2-3 times faster.

2. Updated configure so that --enable-profiling is passed down into libspud so that excessive calls to spud can be more easily monitored.
Fixing bug #1262890: Individual lagrangian detectors are initialised with wrong names, causing detector I/O to fail in parallel.
Fixing re-initialisation of detector names from checkpoint.
A couple of small changes in a test to make it compatible with Python 2.6 on
Red Hat 6.
Minor fix to landslide test. We don't need griddata
Adressing bug 1260019 through improved detector buffer handling

Use separate send and receive buffers for each target proc 
in exchange_detectors() to avoid buffer corruption.
Change only in test: having checked with Matt (test owner), relaxing tolerance
to pass on Ubuntu Trusty.
Fixes for fluidity with petsc 3.4:
  
* MatRestoreRow() now zeros ncols upon return so we have to make sure we put the call after the last use of ncols
* the error handler in the test_petsc_csr_matrix unittest is moved inside petsc_tools - so we can use a module 
  variable to test whether it has been called or not.
Commit purely in tests: On Rhodri's advice, modifying test criteria to accept
both PETSc 3.1 and PETSc 3.4 solver iteration values.
Change in tests only: typo in previous commit set a ridiculous test value.
Commit in test only: Minor tolerance relaxation.
Change only in test: On Cian's advice, until the gmsh team respond with a more
useful fix, altering the geo file slightly to get the test to pass here. This
should be reverted when gmsh is fixed.
Reverting 4310 as it had the unintended effect of breaking trunk on precise.
Correcting the fix for the gmsh failures on trusty.  Temporary: should be reverted if/when gmsh responds.
Speedup vtudiff by only setting up the probe once (instead of once per field).
Remove "field manipulation" methods from vtu class.

These are methods are all vectorial operations like SubFieldFromField that basically perform fieldA-fieldB in a very inefficient way. You should simply use numpy vector operations here.
relaxing some test tolerances to pass since the upgrade to Petsc 3.4.
Merge from trunk