More useful execution log output

[josteinaj]

Moved from snaekobbi/issues#29:

This is some information that might be useful for braille experts to have:

• What happens during volume breaking
• Consequences due to hyphenation and long words either not fitting on a line, causing orphan/widows, etc.
• Characters that cannot be translated to braille due to them not being present in the braille table.
• What happens to tables, how are they laid out, when do they go from being rendered in one way as opposed to another way
• The location in the input file for all these messages
• In addition to being output in the execution log, summarize relevant issues and warnings in a job report, including the number of times each type occured
• How far into the book the conversion is (page number or anything else that can be counted, maybe say for each 100th paragraph something like "Processed {N*100} paragraphs...")
• What part of the conversion is currently being performed (translation, layout, volume breaking, etc.)
• Remove or hide warnings and errors that are expected, does not add any useful information, and is confusing for end-users