Removes `package.hpp`
Removes `Component::package()` method and refactors accordingly
Merge branch 'master' into addressing
Escapes quotes in error messages
Gets the request HTTP method
Adds the `input` virtual method to `Contexts`
Adds `render_input` method to `Stencil`
Adds `input` to `RContext`; other changes
Adds server shutdown to R extension exit
Adds `render_finalise` method
Adds `inputs` method to stencils; refactoring elsewhere
Refactors stencil `pars` and `inputs` methods
Renames `py/stencila/python-context.py` for consistency
Implements `input` method for `PythonContext`
Renames some files
Fixes to Python package
Tidy up
Merge branch 'addressing' into develop
Renaming of RContext files
Removed `Package` class from Python package; uses `Component` class for tests instead