Stop displaying "//" in paths if src or dst end by "/"
Move ext/ into src/

This changes reduce a bit the main directory's
pollution
Stop trying to render non-template HTML files

This change avoid errors dues to non-template HTML files in the sources.
Update CHANGELOG
dynamic mode doesn't need the ‘prismic-dynamic’ meta
Create `example/` directory
sort gitignore
Split gulpfile.js (hide internals)

This change allows to present a clean gulpfile.js
that is not scary and easy to update
Remove generate.js file

It is useless since we can do the same thing with
`gulp`.
Update CHANGELOG
changelog: Remove git refs

Theses refs weren’t really easy to read and forced
to commit twice for each modification (one for the
change and one for the Changelog), plus they don’t
play well with `git rebase`.

They are still available in GitHub’s releases.
Rename task ‘dev’ into ‘serve’
gulp: Fix paths

Every paths were relative, so library generation
and source watching was only working if called in
a specific directory.

Paths relative to source are now global (using the
`src/task/gulp.js` file as reference) so it can now
be called from any place.
browser: dyn mode: Fix 1st URL change

When calling `http://localhost:8282/?a=2`, the URL
was changed into `http://localhost:8282/undefined?a=2`,
which is not only ugly, it is also a unusable URL.
readme: Document “dynamic browser mode”