* Add if around stub summary creation
Check if an existing SUMMARY.md is present to prevent overwriting it
with the stub SUMMARY.md.
[#832]
* Add test for existing SUMMARY.md
* Added a mechanism for creating alternate backends
* Added a CmdRenderer and the ability to have multiple renderers
* Made MDBook::load() autodetect renderers
* Added a couple methods to RenderContext
* Converted RenderContext.version to a String
* Made sure all alternate renderers are invoked as `mdbook-*`
* Factored out the logic for determining which renderer to use
* Added tests for renderer detection
* Made it so `mdbook test` works on the book-example again
* Updated the "For Developers" docs
* Removed `[output.epub]` from the example book's book.toml
* Added a bit more info on how backends should work
* Added a `destination` key to the RenderContext
* Altered how we wait for an alternate backend to finish
* Refactored the Renderer trait to not use MDBook and moved livereload to the template
* Moved info for developers out of the book.toml format chapter
* MOAR docs
* MDBook::build() no longer takes &mut self
* Replaced a bunch of println!()'s with proper log macros
* Cleaned up the build() method and backend discovery
* Added a couple notes and doc-comments
* Found a race condition when backends exit really quickly
* Added support for backends with arguments
* Fixed a funny doc-comment
This rolls all "create missing" handling into BuildConfig, and moves the
build-dir option from the "book" table to the "build" table. Some
documentation cleanup surrounding the build table is also updated.
ThePuzzlemaker
Eric Huss
Sergey Golovin
lzutao
Bas Bossink
Matt Ickstadt
Bastien Orivel
Michael Bryan
Chris Spiegel
Pratik Karki