evolvecmd: pass evolvestate object to _solve* functions This patchs adds an argument evolvestate to _solve* functions. This will help us in having one evolvestate object which we can pass around various functions and keep storing what's going on.

evolve: create a state object in all case Let's create a state object even when we are not in the continue mode. This will help us passing the state object to rest of the functions.

branching: merge with stable

grab: preserve phase of the grabbed changeset This patch fixes the wrong behavior of loosing secret phase of the grabbed changeset.

tests: add a test showing grabbing of secret changeset turn it into draft This patch adds a test showing wrong behavior of `hg grab` command which looses the secret phase while grabbing a secret changeset.

grab: add grab info to cmdutil.afterresolvedstates This will help us in showing how to continue the grab when user resolves all the conflicts.

evolve: add evolve info to cmdutil.afterresolvedstates Adding evolve info to cmdutil.afterresolvedstate will improve the ui when we run into merge conflicts while evolving. Once we resolve all the conflicts using `hg resolve`, this will show a message saying "continue: hg evolve --continue". Other extensions like rebase and shelve also use it and it's very helpful.

doc: add link to roadmap Add a link to the Evolution roadmap in the main page of the documentation.

evolve: move the evolve command to evolvecmd.py This patch moves finishes the code movement by moving the evolve command to evolvecmd.py.

evolve: move _orderrevs() function evolvecmd.py _orderrevs() is a function which is used to order the revs in which the instability needs to be solved if we have multiple revisions to resolve.