Prepare v4.0.4. (ethereumjs#818)

This version just replaces a tilde dependency with a caret one.

common: version bump 1.5.2

docs: update

Merge pull request ethereumjs#740 from ethereumjs/common/release-v151

common: Release Common 1.5.1

Merge pull request ethereumjs#649 from ethereumjs/new-release

New release v4.1.3

Merge pull request ethereumjs#649 from ethereumjs/new-release

New release v4.1.3

Merge pull request ethereumjs#637 from ethereumjs/update-to-muir-glac…

…ier-and-release

New release v4.1.2, dependency updates + simple test for MuirGlacier support

Merge pull request ethereumjs#637 from ethereumjs/update-to-muir-glac…

…ier-and-release

New release v4.1.2, dependency updates + simple test for MuirGlacier support

Merge pull request ethereumjs#190 from ethereumjs/update-common-and-n…

…ew-release

New release v2.1.2, updated Common dependency (MuirGlacier)

Merge pull request ethereumjs#142 from ethereumjs/block-update-and-ne…

…w-release

New release v4.0.3 (MuirGlacier), block and common updates