* feat: [CDE-572]: Using features for devcontainers. Adding changes to parse features from the devcontainer.json and build a new docker image from them. Also adding the support for new devcontainer.json properties- init, privileged, capAdd, securityOpt, mounts. Adding support for three runArgs- privileged, capAdd, mount. Also making the DownloadFeature method context aware, cancelling the goroutines when the ctx is cancelled.
* Changes to support sorting and building.
* Updating go.mod
* feat: [CDE-572]: Adding changes to support features. Changes to support the features property in the devcontainer.json, download features from OCI repos and http(s) URLs as tarballs and parse them to devcontainer-feature.json, resolve them and apply user options. Also added a change to use an OS library to remove comments from the json files.
* feat: [CDE-572]: Adding changes to support features. Changes to support the features property in the devcontainer.json, download features from OCI repos and http(s) URLs as tarballs and parse them to devcontainer-feature.json, resolve them and apply user options. Also added a change to use an OS library to remove comments from the json files.