Update version to 0.3.4

Update Cargo.lock, run rustfmt

Update version to 0.3.2

This also updates Cargo.lock

Fix crash when listing custom instruments

- closes cmyr#14

Update deps, prepare for new release

Mention --bench in readme

Tweak travis, again

Use cargo's pretty printing for diagnostics

Also generally improves diagnostic messages and docs, and cleans
up (slightly) how we handle the --args option

Includes bump to 0.1.2

Touchup readme & Prepare 0.1.1