simplify option object names

SNES: Fixed makefile for nleqerr linesearch

Make the citation data static.

Eliminate an unnecessary C99ism

Implement Barry and Matt's suggestions.

moved PetscOptionsObject from global variable to local variable in functions

manual merge of conflict

Implement the NLEQ-ERR linesearch of Deuflhard (2011).

Remove XXXRegisterAllCalled from public interface.

All XXXRegisterAll() methods are now idempotent, so a boolean indicating
whether they can be called or not is no longer necessary.

Merge branch 'maint'

Conflicts:
config/BuildSystem/config/packages/ml.py
src/ksp/pc/impls/mg/mg.c

fix formatting of some manual pages
specifically remove use of $ from the middle of parameter or options lists

Merge branch 'barry/fix-options-default'

Conflicts:
src/ksp/ksp/examples/tutorials/ex52.c

update use of PetscOptionsBool() to not rely on default setting automatically

cleanup of use of PetscOptionsInt and friends including use of flag final argument

Merge branch 'maint'

Provide additional information in manual pages for line search algorithms

Reported-by: Patric Farrell <patrick.farrell@maths.ox.ac.uk>

MatGetVecs() and KSPGetVecs() replaced with MatCreateVecs() and KSPCreateVecs()
since they are creators not getters