Outdated reference to godep -save=false in README.md / Overview

[dmitris]

Overview in README.md says: Glock is similar to "godep -copy=false". However, godep no longer supports the -copy=false parameter:

$ godep save -copy=false
godep: flag unsupported: -copy=false
Usage: godep save [-r] [packages]

Run 'godep help save' for help.

See also:

• https://github.com/tools/godep/blob/master/save.go#L65
• "Making godep save always copy code" proposal: https://docs.google.com/document/d/1Dxo9PHfNVETus0UCAuviysZZAr2Hv_vPBMK1-9jBU4M/edit#heading=h.x62avzkxk8v8
• https://github.com/tools/godep/pull/118

It would be good to update the overview (possibly just remove the sentence and reference to godep).

[robfig]

Thanks for the note!