make convert(Nullable{T}, ::Nullable) return a Nullable{T}
Add (c)transpose for Givens and Rotation types. Let AbstractMatrix throw on (c)transpose to avoid silent errors when (c)transpose is not implemented for a matrix type. Add some tests. Remove r property from Givens type and return it from givens method.
Use concrete typing on the indexes tuple for SubArray construction

This works around bugs due to #8504.
Docs: fix misc errors introduced recently
Don't export deprecated TcpSocket, IpAddr
These weren't exported in 0.3
Closes #9492
Handle undef refs in jl_copy_ast, fixes #9475

[ci skip] checked on branch fix9475
passed osx
passed linux except for some network issue cloning package.
Add isless(::Ptr, ::Ptr) and tests

Can be useful to check whether a pointer is in a memory range,
e.g. for arrays. Also add tests for pointer arithmetic.
Clarifications to making changes to base & test

Inspired by https://github.com/JuliaLang/julia/issues/9493#issuecomment-68352856
fix missing left-shift in rand(r, Float16) from f1ab1c98
Merge pull request #9466 from JuliaLang/anj/notr2

Fix transpose for arrays
Merge pull request #9495 from mlubin/ipaddr

Don't export deprecated TcpSocket, IpAddr
Merge pull request #9483 from JuliaLang/nalimilan/ptr

Add <(::Ptr, ::Ptr)
Merge pull request #9462 from JuliaLang/rf/nullable-convert

make convert(Nullable{T}, ::Nullable) return a Nullable{T}