Omit comments preceded by a dash

[kashav]

For #15.

Doesn't buffer any comment that is preceded by a dash (-). To omit a target with multiple comments, every comment requires a -. Any target with all comments omitted is not displayed in the help dialogue. View examples below.

# Start the dev server.
#
# Note that the API server must
# also be running.
start:
	@gopherjs -m -v serve --http :3000 github.com/tj/docs/client
.PHONY: start

# Start the API server.
api:
	@go run server/cmd/api/api.go
.PHONY: api

#- Display dependency graph.
deps:
	@godepgraph github.com/tj/docs/client | dot -Tsvg | browser
.PHONY: deps

# Display size of dependencies.
#- Any comment preceded by a dash is omitted.
size:
	@gopherjs build client/*.go -m -o /tmp/out.js
	@du -h /tmp/out.js
	@gopher-count /tmp/out.js | sort -nr
.PHONY: size

$ mmake help

  api     Start the API server.
  size    Display size of dependencies.
  start   Start the dev server.

$ mmake help -v start

  start:
    Start the dev server.

    Note that the API server must
    also be running.

$ mmake help -v size

  size:
    Display size of dependencies.

$ mmake help -v deps

[tj]

thanks :D