[l10n] Enable lingui, string extraction (#810)

* l10n: add lingui, configure, update .babelrc, add gettext:extract & gettext:compile tasks

pretty much just adds default lingui config and deps

* run gettext:extract - added a t`` to a single string, ran extract, added .po to prettierignore

* run gettext:compile - translate single string, compile, add code to activate the translation

* l10n.ts: list available locales, use navigator.languages to pick, default to en

* more l10n - plural & t

get_human_size - use plural correctly for the number of bytes
  czech translation should have 3 plurals, english 2

paths - use t`` now

+extract, clean old string, translate, compile

* Replace _`str` with t`str`

    perl -i -npe 's/\b_\`/t\`/g' src/**

* Remove window._ temporary l10n global

* import { t } everywhere where used

    rg '\bt`'  | cut -f1 -d: | sort -u | while read fn; do (echo '0a'; echo 'import { t } from '\''@lingui/macro'\'';'; echo '.'; echo 'wq') | ed "$fn"; done

* tsconfig - set module 2020 to allow dynamic imports

    src/l10n.ts:13:30 - error TS1323: Dynamic imports are only supported when the '--module' flag is set to 'es2020', 'esnext', 'commonjs', 'amd', 'system', or 'umd'.

    13   const { messages } = await import(`src/../locale/${locale}.js`);
                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* Fix trailing spaces in translations

extraction trims trailing whitespace

detect:

    rg \\bt'`'.*' `'

fixed all of them by adding params inside, or adding and extra `{' '}` react bit

* entry*: add I18nProvider around App

needed for Trans

* src/ use Trans where appropriate

* get better param names when using vars

* gettext:extract

* cs.po: manual fixup bytes example

* update list of languages to en,es,fr,nl,ja,zh, regenerate

Author: himdel

.babelrc

@@ -8,5 +8,6 @@
         "@babel/plugin-syntax-dynamic-import",
         "@babel/plugin-transform-runtime",
         "babel-plugin-lodash",
+        "babel-plugin-macros",
     ]
 }

.linguirc

@@ -0,0 +1,9 @@
+{
+  "catalogs": [{
+    "path": "<rootDir>/locale/{locale}",
+    "include": ["<rootDir>/src"]
+  }],
+  "format": "po",
+  "locales": ["en", "es", "fr", "nl", "ja", "zh"],
+  "sourceLocale": "en"
+}

.prettierignore

@@ -8,3 +8,4 @@ Dockerfile
 *.md
 *.png
 *.mp4
+*.po