First take on new design of linalg
New structure without MATLAB compatibility
Merge branch 'master' into anj/linalg2
Create a base/linalg directory for all the linear algebra code.
Refactor dense.jl and move special matrices into different files.
Merge branch 'master' into anj/linalg2

Conflicts:
	base/deprecated.jl
Put factorizations into their own file.
BunchKaufman factorizations are in a separate file.
Move arpack from extras into base/linalg
Merge branch 'master' into anj/linalg2
Move suitesparse.jl from extras to base/linalg
Merge branch 'master' into anj/linalg2

Conflicts:
	base/linalg_dense.jl
	test/Makefile
	test/extra.jl
Add vector methods to fix #2431 and move functions for general matrices to dense.jl from factorizations.jl.
Merge branch 'master' into anj/linalg2
Merge branch 'master' into anj/linalg2
Added extractors for components of the UmfpackLU type and tests for same.
Merge branch 'master' into anj/linalg2

Conflicts:
	base/linalg_dense.jl
Merge branch 'master' into anj/linalg2

Conflicts:
	base/deprecated.jl
	extras/suitesparse.jl
import Base.convert in suitesparse.jl (from master)
Merge branch 'master' into anj/linalg2
Merge branch 'master' into anj/linalg2