revset id(): fix error text to say "id wants..." instead of "rev wants..."

keyword: only use expensive fctx.cmp when needed Restrict expensive cmp to cases when: - comparing against working directory and - encode filters active or - path is configured for keyword expansion

context: narrow down filter special case in filectx.cmp() cmp via filelog when encode filters are present, but only when actually comparing to the working directory.

incoming: unify code for incoming and graphlog.incoming

incoming: rename variable Groundwork so that incoming and graphlog.incoming code look the same and get easier to unify.

import: only the first hg patch marker should be processed (issue2417) Proper use of the hgpatch state variable had been lost in the final edits of d7452292f9d3 - now it works more like intended.

backout: provide linear backout as a default (without --merge option) This changes backouts changeset to retain linear history, .e. it is committed as a child of the working directory parent, not the reverted changeset parent. The default behavior was previously to just commit a reverted change as a child of the backed out changeset - thus creating a new head. Most of the time, you would use the --merge option, as it does not make sense to keep this dangling head as is. The previous behavior could be obtained by using 'hg update --clean .' after a 'hg backout --merge'. The --merge option itself is not affected by this change. There is also still an autocommit of the backout if a merge is not needed, i.e. in case the backout is the parent of the working directory. Previously we had (pwd = parent of the working directory): pwd older backout auto merge backout --merge auto commit With the new linear approach: pwd older backout auto commit backout --merge auto commit auto: commit done by the backout command merge: backout also already committed but explicit merge and commit needed commit: user need to commit the update/merge

update: use revsingle to enable use of revsets as update targets (issue1993)

test-url: skip test when ssl module is unavailable

test-url: remove trailing whitespace