CS[-][space] manage meta-spaces to filter comments, etc..

Usage: CS [*] [+-][metaspace|addr] # Manage metaspaces

• CS display metaspaces
• CS * select all metaspaces
• CS metaspace select metaspace or create if it doesn't exist
• CS-metaspace remove metaspace
• CS-* remove all metaspaces
• CS+foo push previous metaspace and set
• CS- pop to the previous metaspace
• CSr newname rename selected metaspace