Build, translations & transifex

* We have `pot` files in github, is this necessary?
https://github.com/geonetwork/doc/tree/develop/_build/locale

* What files transifex is using? Looks to be `pot`, right?

Transifex is using pot files. See https://github.com/geonetwork/doc/blob/develop/Makefile#L68

* How do we synch transifex with github?

Use
```shell
make update_translations
```

* Is it automatic?

* When we change a letter in a rst file in English, what happens on transifex ? I'm afraid we will lose the translations as the msgid is the english phrase ?

```pot
msgid "This section gives some guidelines to write consistent documentation for |project_name|."
msgstr ""
```

* Is there a way to build `rst` files in a language from `pot`?

@Delawen maybe you've some answers ? thanks.