merge: add --tool argument to merge and resolve These arguments are shorthand for --config ui.merge, but they also override HGMERGE if it is found in the user's environment.

patchbomb: move command option help from the extension (patchbomb) to the command (email)

alias: fail gracefully when invalid global options are given (issue2442) This patch modifies the check for shell aliases to prevent crashing when an invalid global option is given. When an invalid global option is given the check will simply return and let the normal error handling for this case happen.