multilingual javascript

[micuat]

from #37 (comment)

Currently the demo javascripts are hardcoded with english texts but they should be translated too. I tested i18next and it seems working well, which can be found in my branch:
master...micuat:js-multilng

[micuat]

@genekogan in this branch I added i18next library for multilingual javascript (only for simple forward pass demo with en/fr by google translate): master...micuat:js-multilng

One observation is that, in the branch above I naively moved all the variables to be input to i18next

set_text_panel(parent.description_panel_div,
	i18next.t('segment7', {in0: y_correct, in1: y_correct.toFixed(2), in2: acts[2][0].toFixed(2), in3: error.toFixed(3)}),
	true);

but maybe latex equations should be formatted before passing to i18next like this

set_text_panel(parent.description_panel_div,
	i18next.t('segment7', {in0: y_correct, in1: '\\begin{aligned} \
	\\text{mse} &= ('+y_correct.toFixed(2)+' - '+acts[2][0].toFixed(2)+')^2 \\\\ \
	\\text{mse} &= '+error.toFixed(3)+' \
	\\end{aligned}'}),
	true);