Add subroutines to reset all user numbers for elements in a mesh

Tracker item: 2487
Implementing two new strain energy functions

EQUATIONS_SET_TRANSVERSE_ISOTROPIC_ACTIVE_SUBTYPE
for transversely isotropic, active materials
EQUATIONS_SET_TRANS_ISOTROPIC_ACTIVE_TRANSITION_SUBTYPE
for transversely isotropic, active materials with material transition
Merge branch 'master' of https://github.com/OpenCMISS/cm

Conflicts:
	src/equations_set_constants.f90
	src/finite_elasticity_routines.f90
	src/opencmiss.f90
Merge branch 'master' of https://github.com/OpenCMISS/cm
Implementing one new strain energy function

EQUATIONS_SET_TRANSVERSE_ISOTROPIC_POLYNOMIAL_SUBTYPE
for transversely isotropic materials
Minor fixes according to the previous commits
Minor bugfix
minor bugfixes
Merge branch 'master' of https://github.com/cbleiler/cm
Merge pull request #176 from el-tomo/master

further development of coupled bioelectric finite elasticity
Merging cbleiler pull request #185
Merge pull request #188 from chrispbradley/master

Merging pull request #185
Merge branch 'master' of https://github.com/xyan075/cm into xyan075-master
Merging pull request #183 plus fixes for the comments in the pull request
Bug fixes.
Merge pull request #189 from chrispbradley/master

Merging pull request #183
Merge branch 'master' of https://github.com/OpenCMISS/cm
commented out potentially superfluous averaging - will probably be removed in a later commit
minor fixes in documentation