The `version_name` manifest field was being used on Chrome to store the
build type. However, Chrome intended this field to be a full
representation of the version, for display purposes. This was evident
when uploading this version to the Chrome Web Store, because it used
`flask` as the entire version.
Instead the `version_name` field now includes the full SemVer version
string. The version parsing code within the build script and in the
wallet itself have been updated accordingly.
The extension version used throughout the wallet is now normalized to a
SemVer-compliant version that matches the version used in
`package.json`. We use this version for display on the "About" page,
and we attach it to all error reports and metric events, so it's
important that we format it consistently so that we can correlate
events on the same version across different browsers.
This normalization step is necessary because Firefox and Chrome both
have different requirements for the extension version, and neither is
SemVer-compliant.