* ref: embed portion of files
* fix: readd pkger
* ref: embed version.txt
* fix: wrong mail template import path
* refactor: get rid of sql-migrate
refactor: get rid of pkger in favor of go embed (resolve#164)
* chore: remove unused var [ci-skip]
Co-authored-by: Ferdinand Mütsch <ferdinand@muetsch.io>
Steven Tang