dep init fails on for packages with multiple dashes in the version

[carolynvs]

I've opened an issue with deps' semver library: Masterminds/semver#59.

When our semver lib parses the comment v1.3.1-1-gf12c623 as a constraint, it is not returning an error, nor a valid constraint, resulting in wonky resolution like this:

attempt github.com/fsnotify/fsnotify with 1 pkgs; 32 versions to try
(51)      try github.com/fsnotify/fsnotify@v1.4.2
(52)  ✗   github.com/fsnotify/fsnotify@v1.4.2 not allowed by constraint :

This is also a problem for:

• github.com/garyburd/redigo @ v1.0.0-1-gb8dc900
• github.com/gogo/protobuf @ v0.4-3-gc0656edd
• github.com/google/cadvisor @ v0.26.0-2-gb971fd1
• github.com/jteeuwen/go-bindata @ v3.0.7-72-ga0ff256
• github.com/karlseguin/ccache @ v2.0.2-5-g3ba9789
• github.com/lpabon/godbc @ v1.0-1-g9577782
• github.com/magiconair/properties @ v1.7.0-4-g61b492c
• github.com/mistifyio/go-zfs @ v2.1.1-5-g1b4ae6f
• github.com/mvdan/xurls @ v0.8.0-14-g1b768d7
• .... I give up, this is used a lot.

[sdboyer]

eeew, crap, that's super not ok. definitely a bug I'm responsible for, too 😛

[carolynvs]

If I felt bad about every bug that I was responsible for, I would have been forced to leave software a loooong time ago. 😇

[carolynvs]

Fixed via golang/dep#938.