translations: add Qt translation support

This patch adds support to Qt translation using TS files.
It adds also transifex configuration file to support
transifex web translation service, and remove old GNU gettext support.

See https://www.transifex.com/savoirfairelinux/ring

Issue: #78928
Change-Id: I24150fd072796e8658f8e5a2ed6ee477c9e85a18

.tx/config

+[main]
+host = https://www.transifex.com
+
+[ring.lrc_en_ts]
+file_filter = translations/lrc_<lang>.ts
+source_file = translations/lrc_en.ts
+source_lang = en
+type = TS
+

INSTALL

@@ -63,3 +63,12 @@ cmake .. -DCMAKE_INSTALL_PREFIX=<install_dir_of_daemon> [-DCMAKE_BUILD_TYPE=Debu
 make install
 
 You can now link and build the OSX client with Ring daemon and LRC library
+
+Internationalization
+====================
+
+To regenerate strings for translations we use lupdate (within root of the project)
+
+lupdate ./src/ -source-language en -ts translations/lrc_en.ts
+
+Hint: On OSX lupdate is installed with Qt in /usr/local/Cellar/qt5/5.5.0/bin/ when installed with HomeBrew

Messages.sh

-#! /bin/sh
-
-$EXTRACT_TR_STRINGS `find . -path ./build -prune -o -name '*.cpp'` -o $podir/libringclient_qt.pot

config.ini

-#
-# you can use remove, addPo, addDocs, set docs to yes if an app has
-# doc translations, etc.
-#
-
-[libringclient]
-mainmodule   = extragear
-name         = libringclient
-submodule    = network
-folder       = libringclient
-kde_release  = no
-version      = 0.4.0
-docs         = yes
-translations = yes
-gitModule    = yes
-custompo     = libringclient_qt

genpot.sh

-#!/bin/bash
-
-mkdir -p build
-cd build
-if [ -d scripts ]; then
-  cd scripts
-  svn up
-  cd ..
-else
-  svn co svn://anonsvn.kde.org/home/kde/branches/stable/l10n-kde4/scripts
-fi
-cd ..
-mkdir -p po
-IGNORE="/build/" ./build/scripts/extract-messages.sh

release.sh

-#!/bin/bash
-echo 'Make sure config.ini  and all code version refewrences are ready [PRESS ENTER]'
-read
-mkdir -p build
-cd build
-if [ -d "kde-dev-scripts" ]; then
-  cd kde-dev-scripts
-  git pull
-  cd ..
-else
-  git clone http://anongit.kde.org/kde-dev-scripts
-fi
-
-cp ../config.ini ./
-cp kde-dev-scripts/createtarball/create_tarball.rb ./
-ruby create_tarball.rb -n -a libringclient && mv libringclient*.tar.* ../