revset: use spanset.isdescending in multiple simple places We call the method directly instead of duplicating checks. Benchmarks show no performances harmed in the process.

revset: wider definition of ascending and descending for spanset Before this patches, empty spanset were seen as neither ascending nor descending. This is mathematically wrong and create some edges case. We put `isascending` and `isdescending` back on track so we can use them to simplify some of the spanset code. Benchmarks show no performances harmed in the process.

annotate: port to generic templater enabled by hidden -T option If the selected formatter is other than plainformatter, raw data are passed to the formatter. In this case, it isn't necessary (and not possible) to calculate column widths. Field names are substituted to be the same as "log" command. There are a few limitations: - "binary file" message is not included in formatted output. - no data structure for multiple files. all lines are packed to single list.

annotate: split functions to get data without applying text formatting This prepares for porting to generic templater API, where raw data should be passed to the formatter. makefunc() is necessary to build closure in list comprehension.

annotate: remove unused variable in calculation of column widths

annotate: build format string separately from annotation data This prepares for porting to generic templater API. Note that we cannot use '%*s' to pad white spaces because it doesn't take into account character widths, as described in 4f5a6df2af92.