Modernized progress window GUI

Following the refactoring that has been initiated in pdfmasher's
"vala" branch, I pushed more progress window logic into the
core.

The UI code is now a bit dumber than it used to be, and the core
now directly decides when the progress window is shown and
hidden. The "job finished" notification is also directly sent by the
core. Job description update logic is handled by a core gui
textfield.

Job description contsants also moved to the core, triggering
a localisation migration from "ui" to "core".

locale/pt_BR/LC_MESSAGES/ui.po

@@ -13,26 +13,6 @@ msgstr ""
 "Language: pt_BR\n"
 "Plural-Forms: nplurals=2; plural=(n > 1);\n"
 
-#: cocoa/inter/app.py:15 qt/base/app.py:38
-msgid "Scanning for duplicates"
-msgstr "Buscando por duplicatas"
-
-#: cocoa/inter/app.py:16 qt/base/app.py:39
-msgid "Loading"
-msgstr "Carregando"
-
-#: cocoa/inter/app.py:17 qt/base/app.py:40
-msgid "Moving"
-msgstr "Movendo"
-
-#: cocoa/inter/app.py:18 qt/base/app.py:41
-msgid "Copying"
-msgstr "Copiando"
-
-#: cocoa/inter/app.py:19
-msgid "Sending to Trash"
-msgstr "Movendo para o Lixo"
-
 #: cocoa/inter/app_me.py:34
 msgid "Removing dead tracks from your iTunes Library"
 msgstr "Removendo faixas sem referência da sua Biblioteca do iTunes"
@@ -88,10 +68,6 @@ msgstr ""
 msgid "The iPhoto application couldn't be found."
 msgstr "O aplicativo iPhoto não foi encontrado."
 
-#: qt/base/app.py:42
-msgid "Sending files to the recycle bin"
-msgstr "Enviando arquivos para o Lixo"
-
 #: qt/base/app.py:95
 msgid "Quit"
 msgstr "Encerrar"
@@ -125,14 +101,6 @@ msgstr "Buscar Atualizaçõs"
 msgid "Open Debug Log"
 msgstr "Abrir Registro de Depuração"
 
-#: qt/base/app.py:217 cocoa/base/en.lproj/Localizable.strings:0
-msgid ""
-"A previous action is still hanging in there. You can't start a new one yet. "
-"Wait a few seconds, then try again."
-msgstr ""
-"Ainda há uma ação em execução. Não é possível iniciar outra agora. Espere "
-"alguns segundos e tente novamente."
-
 #: qt/base/app.py:257
 msgid "{} file (*.{})"
 msgstr "Arquivo {} (*.{})"
@@ -872,9 +840,3 @@ msgstr "Reduzir/Ampliar"
 #: qt/base/deletion_options.py:46
 msgid " (unsupported)"
 msgstr ""
-
-#~ msgid " (Mac OS X or Linux only)"
-#~ msgstr " (Mac OS X ou Linux somente)"
-
-#~ msgid "Re-Prioritize Results"
-#~ msgstr "Re-Priorizar Resultados"