chore(git): add `tmp` to .gitignore
docs(CONVENTIONS.md): added
docs(license): switch to atx headers
chore(package.json): switch *less*, add *lodash*

Replace *`grunt-recess`* with *`grunt-contrib-less`*. The most recent
version of *Bootstrap* requires a newer *less* compiler than the one
found in *`grunt-recess`*.

Add *`lodash`* to the module list so the *Gruntfile* can use it instead
of the deprecated *`grunt.util._`*.
chore(Cakefile): remove
chore(app): move `src/` to `app/`

The `src/` directory's name could be considered a misnomer, since some of
its contents might be pre-compiled, or binary assets. The top-level `src/`
directory is renamed to `app/`, while the `app/` folder within -- which
only contains source code -- is renamed to `src/`, so for example
`src/app/index.html` is now `app/src/index.html`.
feat(build): numerous changes to the build system

  - Add *lodash* as a required module.
  - Move hardcoded configuration options from `Gruntfile.coffee` to
    `config/build.conf.coffee`.
  - Merge in *Gruntfile* from
    <https://github.com/yearofmoo/angularjs-seed-repo>
  - Switch *`grunt-recess`* configuration to *`grunt-contrib-less`*.
fix(changelog): add missing changelog template
chore(git): remove `src/` directory