Changes:
* Terminate all namespaces with the correct closing comment.
* Make sure argument names in comments match the corresponding parameter name.
* Remove redundant get() calls on smart pointers.
* Prefer using "override" or "final" instead of "virtual". Remove "virtual" where appropriate.
The Swift README states that the minimum CMake version required to build the
Swift project is the same as LLVM's: 3.4.3. Bump the minimum version
used by CMake to correspond to the README.
The main action here is to sink the creation of the installation rule for all of
the swift host tools into this API. In a latter commit, I will use this API to
create include and build rules for add_swift_host_tool.
swift-remote-ast has dependencies that cannot be satisfied by all
of the targets Swift supports. Specifically, the Android target is
unable to link libraries that libRemoteAST depends on, such as uuid.
To fix builds for unsupported platforms, only build remoteast-test
for the host platform.
