doc: describe full help document hierarchy to create a valid link in HTML For example, ":hg:`help config.default-push`" creates an invalid link to "hgrc.5.html#default-push" in HTML, but ":hg:`help config.paths.default-push`" creates a valid link to "hgrc.5.html#paths".

doc: translate from :hg:`help config.SECTION` to a valid link to hgrc.5.html Before this patch, ":hg:`help config.SECTION`" in online help text is translated to a link to "hg.1.html#config.SECTION" in HTML unintentionally. This patch translates from :hg:`help config.SECTION` in online help text to a valid link to "hgrc.5.html#SECTION" in HTML. This patch ignores element(s) under "SECTION" (e.g. "ITEM" of ":hg:`help config.SECTION.ITEM`"), because there is no way to refer directly to it in HTML, yet.

doc: translate from :hg:`help config` to a valid link to hgrc.5.html Before this patch, ":hg:`help config`" in online help text is translated to a link to "hg.1.html#config" in HTML, even though actual "hg help config" shows not help for "hg config" command but "config" help topic, and all of current ":hg:`help config`" expects the latter. This patch translates from ":hg:`help config`" in online help text to a link to "hgrc.5.html" in HTML as expected. This patch also allows ":hg:`help -c COMMAND`" style to link "hg.1.html#COMMAND" for readability.

i18n: calculate correct line number in source of messages to be translated Before this patch, line number in source of the message to be translated is wrong in hg.pot, if corresponded message is placed after ".. DIRECTIVE::", because number of lines related to such directive isn't added to variable "delta", which holds number of untranslated lines in given text. This patch always adds "2" to "delta", because text block is split into translation units by "\n\n".

revsetbenchmark: handle exception case If the revset being benchmarked has an exception, the handling code was encountering an error because the exception did not always have an "output" attribute (I think it's a python 2.7 thing).

merge: minimize conflicts when common base is not shown (issue4447) Previously, two changes that were nearly, but not quite, identical would result in large merge conflict regions that looked very similar, and were thus very confusing to users, and lead people used to other source control systems to claim that "mercurial's merge algorithms suck". In the relatively common case of a new file being introduced in two branches with very slight modifications, the old behavior would show the entire file as a conflict, and it would be very difficult for a user to determine what was going on. In the past, mercurial attempted to solve this with a "very smart" algorithm that would find all common lines, but this has significant problems as described in 2ea6d906cf9b. Instead, we use a "very dumb" algorithm introduced in the previous patch that simply matches lines at the periphery of conflict regions. This minimizes most conflict regions well, though there may still be some degenerate edge cases, like small modification to the beginning and end of a large file.