Added min/max methods for Vector (issue #118)
Added min/max methods for Matrix (issue #118)
Added min/max in rows and columns methods for Matrix (issue #118)
Added min/max in rows and columns methods for SparseMatrix (issue #118)
Fixed double calls of get/set (issue #118)
Added tests for vector (issue #118)
Added tests for min/max in matrix (issue #118)
Added tests for min/max in rows and columns in matrix (issue #118)
merged Maxim's commtrubuton