Merge pull request #34 from ToQoz/fix-binary-exprs

fix BinaryExpr execution method

Merge pull request #30 from ToQoz/support-unary-exprs

feat(gopwt): support some unary ops in assert. (+, -, ^, &, <-)

feat(gopwt): show diff or expected/got if possible

chore(misc): update

fix(gopwt): createRawStringLit with `

before (this is broken):
  createRawStringLit("fo`foo") --- generate code ---> `fo`foo`

after:
  createRawStringLit("foo`bar") --- generate code ---> `foo` + "`" + `bar`

Merge pull request #18 from ToQoz/drop-go1.4-use-go1.4.1

drop go1.4. use go1.4.1 or later