Output improvements

[bmingles]

There are a number of requests that have been made for better output configuration: e.g.

• Add option to remove header and footer messages #89
• Add configuration options for status messages #83

I'd like to address this holistically:

• Use integrated terminal instead of output channel for primary output
• Better control over output

[vishalkumar863]

{ "emeraldwalk.runonsave": { "commands": [ { // Run whenever any file is saved "match": ".*", "cmd": "echo '${fileBasename}' saved." } ] } }

[bmingles]

Merged