Elemental: disable Qt5 so we don't have to pass -I for those include paths
If only the RHSJacobian is provided to TS currently it creates an extra Arhs matrix
in addition to the IJacobian matrix and then the MATAXPY() creates a new matrix on
ever single Jacobian evaluation.

This fix removes any extra matrix creations

[0] 6 4576 MatCreate()
[0] 2 832 MatCreate_SeqAIJ()
[0] 5 68096 MatSeqAIJSetPreallocation_SeqAIJ()

instead of

[0] 16 48384 MatAXPY_BasicWithPreallocation()
[0] 16 24320 MatAXPY_SeqAIJ()
[0] 57 43472 MatCreate()
[0] 19 7904 MatCreate_SeqAIJ()
[0] 6 69616 MatDuplicateNoCreate_SeqAIJ()
[0] 1 1520 MatDuplicate_SeqAIJ_Inode()
[0] 85 1157632 MatSeqAIJSetPreallocation_SeqAIJ()

and this was just with 2 timesteps
Merge branch 'master' into barry/ts-rhsjacobian-only
Varierty of bug fixes and enhancements to fieldsplit
pcfieldsplit coupling uses all degrees of freedom in second space
Barry is an idiot
tao: untabify sources
tao: remove trailing spaces from sources
manual: Fix a grammatical error
vsectionis.c: Fix a comment typo
manual: Fix typo (liek -> like)
plex.c: Fix typo: nubmer -> number
DMPlexStratify: Clarify documentation
snes ex62: Fix incompressibility equation typo
DMPlex: Don't imply we can't handle triangles with 3D coordinates
Mention cell number in another DMPlexComputeCellGeometry error
convert most PetscMalloc() in tao to PetscMalloc1()
more formating of Tao source code
TaoSubsetType should be enum not integer
remove tao-private include directory, private goes into petsc-private
tao: fix negative blas counter in pounders