Modify cmake for Petsc config.
Add PETSc vector interface.
Modify testrunner for PETSc tests. Add PETSc tests.
Add travis configuration.
Add make-target test for the PETSc intreface
Correct/remove spaces.
Updated findPETSc to jedbrown/cmake-modules@d510bc35
PETSc can be found on Max OS X too.

The hard-tab in the generated Makefile is required!

Two CMake-runs are necessary, the first fails, the second succeeds.
Reason seems to be something in find_package_multipass() ...
Change include syntax for lis.h and petscksp.h
A a piece of document to finalizeVectorAssembly
Remove one blank line in some comments of documentation according to Karstens comments
setup of basic structure
setting element status and getting total numbers of nodes and elems
returning active nodes and elements vector
setting status based on mat id and returning active elements for a node
added comments
changed return type for connected active elements of a node to unsigned int
introduced element IDs
Merge pull request #8 from wenqing/PR_petsc_vec

Change include syntax for lis.h and petscksp.h. Documentation. Formatting.
Merge pull request #7 from bilke/petsc

PETSc related cmake changes. MacOS.