refactored Edge class into TemplateLine class
fixed inconsistent indentation
Merge pull request #381 from rinkk/EdgeLineMerge

TemplateLine refactoring
[AL] Forward additional args for local assembly.
[AL] Overloaded SerialExecutor::execute().

The overloaded version takes a third argument. This argument is used
needed properties in the local assembler.
[AL] Overloaded VectorMatrixAssembler::operator().

The overloaded version has a parameter for data needed by the local assembly process.