Improved working of BackupDialog

- improved layout
- automatically switch to output component when start is clicked
- coloured output for succes/error message
- highlighter for pg_dump output that highlights error lines

Note: all output of pg_dump goes to stderr because stdout is reserved for output of the backup data.

pglab/pglab.pro

@@ -24,6 +24,7 @@ SOURCES += main.cpp\
     NotificationListWidget.cpp \
     NotificationModel.cpp \
     NotificationService.cpp \
+    PgDumpOutputHighlighter.cpp \
     QueryResultModel.cpp \
     QueryExplainModel.cpp \
 	CreateDatabaseDialog.cpp \
@@ -88,6 +89,7 @@ HEADERS  += \
     NotificationListWidget.h \
     NotificationModel.h \
     NotificationService.h \
+    PgDumpOutputHighlighter.h \
     QueryResultModel.h \
     QueryExplainModel.h \
 	CreateDatabaseDialog.h \