Start tagging dependencies

[whyrusleeping]

Lets start tagging issues and PRs with what they depend on.

For example:

• depends on Arch Linux User Package #7

or

• depends on logger subsystems are off libp2p/go-libp2p#18

NOTE: if youre actually writing these, omit the asterisk.

If we do this rigorously then we can more easily integrate into @jbenet's dependency visualizer tool

[wking]

The current dependency regex isn't smart enough to detect pre blocks, so your depends lines above show up in the graph ;).

If you want to not match the regexp, put something else in the line. For example, backticks (depends on #7) or a leading *:

• depends on Arch Linux User Package #7

[whyrusleeping]

@wking haha, thanks for the tip