doc: add description about pattern matching against directories Before this patch, there is no explicit description about pattern matching against directories, even though users may understand it from "plain examples" in "hg help patterns". This patch adds description about pattern matching against directories.

revset: add explanation about the pattern without explicit kind Before this patch, online help of "adds()", "contains()", "filelog()", "file()", "modifies()" and "removes()" predicates doesn't explain about how the pattern without explicit kind like "glob:" is treated, even though each predicates treat it differently: - as "relpath:" by "adds()", "modifies()" and "removes()" - as "glob:" by "file()" - as special by "contains()" and "filelog()" - be relative to cwd, and - match against a file exactly ("relpath:" matches also against a directory) This may confuse users. This patch adds explanation about the pattern without explicit kind to these predicates.

revset: use "canonpath()" for "filelog()" pattern without explicit kind Before this patch, revset predicate "filelog()" uses "match.files()" to get filename also for the pattern without explicit kind. But in such case, only canonicalization of relative path is required, and other initializations of "match" object including regexp compilation are meaningless. This patch uses "pathutil.canonpath()" directly for "filelog()" pattern without explicit kind like "glob:", for efficiency. This patch also does below as a part of introducing "canonpath()": - move location of "matchmod.match()" invocation, because "m" is no more used in "if not matchmod.patkind(pat)" code path - omit passing "default" argument to "matchmod.match()", because "pat" should have explicit kind of pattern in this code path

revset: avoid loop for "match.files()" having always one element for efficiency This patch avoids the loop for "match.files()" having always one element in revset predicate "filelog()" for efficiency: "match" object "m" is constructed with "[pat]" as "patterns" argument.