add album cover scaling and caching

go.sum

@@ -20,6 +20,8 @@ github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/denisenkom/go-mssqldb v0.0.0-20181014144952-4e0d7dc8888f/go.mod h1:xN/JuLBIz4bjkxNmByTiV1IbhfnYb6oo99phBn4Eqhc=
 github.com/denisenkom/go-mssqldb v0.0.0-20191124224453-732737034ffd h1:83Wprp6ROGeiHFAP8WJdI2RoxALQYgdllERc3N5N2DM=
 github.com/denisenkom/go-mssqldb v0.0.0-20191124224453-732737034ffd/go.mod h1:xbL0rPBG9cCiLr28tMa8zpbdarY27NDyej4t/EjAShU=
+github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1ei82L+c=
+github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
 github.com/dustin/go-humanize v1.0.0 h1:VSnTsYCnlFHaM2/igO1h6X3HA71jcobQuxemgkq4zYo=
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
 github.com/erikstmartin/go-testdb v0.0.0-20160219214506-8d10e4a1bae5 h1:Yzb9+7DPaBjB8zlTR87/ElzFsnQfuHnVUVqpZZIcV5Y=
@@ -169,6 +171,7 @@ golang.org/x/image v0.0.0-20190220214146-31aff87c08e9/go.mod h1:kZ7UVZpmo3dzQBMx
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067 h1:KYGJGHOQy8oSi1fDlSpcZF0+juKwk/hEMv5SiwHogR0=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
 golang.org/x/image v0.0.0-20190802002840-cff245a6509b/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
+golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
 golang.org/x/image v0.0.0-20200430140353-33d19683fad8 h1:6WW6V3x1P/jokJBpRQYUJnMHRP6isStQwCozxnU7XQw=
 golang.org/x/image v0.0.0-20200430140353-33d19683fad8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
 golang.org/x/mobile v0.0.0-20180806140643-507816974b79 h1:t2JRgCWkY7Qaa1J2jal+wqC9OjbyHCHwIA9rVlRUSMo=