[fix] Make build reproducible (generate same CSS and JS files - e.g; templates.js file)

[fix] Transfer: display loading spinner when loading wallet
[fix] Wallets: display alert when unable to remove secondary wallet + simplify code

Spanish translation pluginmap by @kapis

See merge request clients/cesium-grp/cesium!618

# Conflicts:
#   www/plugins/es/i18n/locale-es-ES.json

Spanish translation by @kapis

See merge request clients/cesium-grp/cesium!617

# Conflicts:
#   www/plugins/es/i18n/locale-es-ES.json

[fix] Enforce use of angular-translate, when some keys are not defined (avoid error "translationId must be a not empty string")

# Conflicts:
#   www/plugins/es/i18n/locale-es-ES.json