Rename init_debug() → enable_debug(), add documentation.

src/log.cpp

@@ -81,7 +81,7 @@ void init()
     blog::add_common_attributes();
 }
 
-void init_debug()
+void enable_debug()
 {
     global.textlog->set_filter(blog::trivial::severity == sev::debug);
 

src/log.hpp

@@ -45,9 +45,11 @@ struct global_variables
 BOOST_LOG_INLINE_GLOBAL_LOGGER_DEFAULT(
     logger, boost::log::sources::severity_logger_mt<sev>)
 
+//! Call this before doing any logging.
 void init();
 
-void init_debug();
+//! Enable debug logging. Call after init().
+void enable_debug();
 
 } // namespace epubgrep::log