client: better ebook error tracking; exept on duplicates
client: removed update CLI command
client: better dedrm tools check logic
client: calculate MD5 as part of full scan
client: always show progress bar during scan
client: aggressive filling of local cache
tests: remove coupling to update_library() from some tests
tests: completely disable broken integration tests
client: refactored metadata/md5 code into new EbookObject
client: more prereqs only needed for sync command..
client: better reporting on duplicates
tests: updated prereqs tests refs df3c25ae
tests: updated client tests to use EbookObject and helper
client: minor refactor to setup_auth_user in prereqs
client: improve calibre ebook-meta prereqs for v2 release
tests: updated tests after ebook_obj refactor
client: identifier metadata extract bug fix and test
client: don't calculate MD5 twice..
client: filename is not needed as part of EbookObject
client: smarter serialisation of EbookObjects from/to the cache