Add attributes to `core.sys.posix.{arpa.inet,sys.uio}`.
change install target to match current release structure
fix Issue 13084 - ModuleInfo.opApply delegate expects immutable parameter

- cast to mutable
deprecate mutating assignment to ModuleInfo

- It's not possible to deprecate default construction
  as `deprecate this()` is not allowed.

- Deprecating copy-construction `deprecate this(this)`
  results in a lot of false deprecation warnings
  due to compiler generated functions.
Merge pull request #908 from braddr/install-fix

change install target to match current release structure
Fix install directory on Mac OS X
Merge pull request #878 from denis-sh/add-attributes-to-`core.sys.posix.{arpa.inet,sys.uio}`

Add attributes to `core.sys.posix.{arpa.inet,sys.uio}`.
Merge pull request #910 from tom-tan/fix-install-dir-on-osx

Fix install directory on Mac OS X
Merge pull request #909 from MartinNowak/fix13084

fix Issue 13084 - ModuleInfo.opApply delegate expects immutable parameter