packages/core: add permission management module

Permissions have been long ignored in Halibot, largely because there hasn't
been a convenient way to manipulate them. This commit adds a core module
to expose some commands for runtime permission management.

packages/core/__init__.py

@@ -1,2 +1,3 @@
 
 from .help import Help
+from .perm import PermissionManager

packages/core/perm.py

@@ -0,0 +1,31 @@
+from halibot import CommandModule
+from halibot.halauth import hasPermission
+
+class PermissionManager(CommandModule):
+	def init(self):
+		self.commands = {
+			"grant":  self.grant_,
+			"revoke": self.revoke_,
+		}
+
+	@hasPermission("PERM_GRANT", reply=True)
+	def grant_(self, argv, msg=None):
+		try:
+			ri, identity, perm = argv.split(" ")
+		except:
+			self.reply(msg, body="Must be in the form '<ri> <identity> <perm>'")
+			return
+
+		if self._hal.auth.grantPermission(ri, identity, perm):
+			self._hal.auth.write_perms()
+
+	@hasPermission("PERM_REVOKE", reply=True)
+	def revoke_(self, argv, msg=None):
+		try:
+			ri, identity, perm = argv.split(" ")
+		except:
+			self.reply(msg, body="Must be in the form '<ri> <identity> <perm>'")
+			return
+
+		if self._hal.auth.revokePermission(ri, identity, perm):
+			self._hal.auth.write_perms()