Dependency on JSV breaks electron-builder

[rdev]

Running electron-builder fails in projects that have jsonlint dependency, because jsonlint depends on JSV which has broken "dependencies" field causing electron-builder to freak out and crash.

JSV hasn't been updated in 7 years and is seemingly abandoned (the PR fixing the dependencies field has been open since July), it's probably not a good idea to depend on it

[prantlf]

I needed some bugfixes and extensions to jsonlint and did them in my fork. I released the changes as a new NPM module @prantlf/jsonlint. Replacing the JSV validator with ajv, which supports JSON Schema drafts 04, 06 and 07, was one of them. I dropped the support for draft 03, which is not available in ajv.