Hard-coded configuration paths in tools

[pacien]

Paths to main configuration and registration files are hard-coded in some scripts.
It should be possible to specify the path to those files as command line parameters.

• https://github.com/Half-Shot/matrix-appservice-discord/blob/master/tools/addRoomsToDirectory.ts#L72
• https://github.com/Half-Shot/matrix-appservice-discord/blob/master/tools/addbot.ts#L25
• https://github.com/Half-Shot/matrix-appservice-discord/blob/master/tools/adminme.ts#L93
• https://github.com/Half-Shot/matrix-appservice-discord/blob/master/tools/chanfix.ts#L67
• https://github.com/Half-Shot/matrix-appservice-discord/blob/master/tools/ghostfix.ts#L76

[pacien]

#508 merged.