Non-null Types and Non-null By Default (NNBD)

Dart Enhancement Process (DEP) proposal for non-null types and non-null by default. The full proposal is available in two formats:

PDF, or
markdown (autogenerated, DO NOT EDIT).

Original markdown sources for the proposal are under doc-src.

If you make changes and want to generate the PDF, then follow these instructions. (When submitting a Pull Request, there is no need to submit the PDF or .md under doc.)

To build the proposal you will need Pandoc, which can be installed as a brew cask as follows:
```
$ brew cask install pandoc
```
(The pandoc cask takes minutes to install, against hours for the homebrew pandoc Formula.)
We also have a simple custom Pandoc filter that requires a node package so run:
```
$ npm install
```
To generate a PDF run:
```
$ make
```

DEP-non-null

Commits

v0.6.0 updates (2015-06-26)

Project stats update following discussion; analyzer code has 10 anno/KLOC

v0.5.0 updates (2015-06-24)

Remove execute permission from text files

pandoc filter update: make math look better in md format

Add alt: Ensuring `Object` is non-null by making `Null` a root too

README

Non-null Types and Non-null By Default (NNBD)