Revert "Speed up loading dependencies by removing .modified checks"
Revert "Speed up loading dependencies by removing .modified checks"

This reverts commit f55e113290a3a931c7960fb404cdb012872e642c.

While we do indeed compare the checksums of the precomp files, we still need
to check if the source file has changed. So unfortunately, we cannot get rid
of this rather expensive check.
Brings GTK::Simple's loading time back up to 257ms.

nbrown/rakudo,lucasbuchala/rakudo,jonathanstowe/rakudo,samcv/rakudo,tony-o/rakudo,lucasbuchala/rakudo,tbrowder/rakudo,labster/rakudo,salortiz/rakudo,raydiak/rakudo,salortiz/rakudo,softmoth/rakudo,rakudo/rakudo,labster/rakudo,awwaiid/rakudo,labster/rakudo,salortiz/rakudo,labster/rakudo,raydiak/rakudo,jonathanstowe/rakudo,rakudo/rakudo,lucasbuchala/rakudo,tbrowder/rakudo,Gnouc/rakudo,salortiz/rakudo,sjn/rakudo,usev6/rakudo,usev6/rakudo,lucasbuchala/rakudo,tbrowder/rakudo,raydiak/rakudo,tbrowder/rakudo,samcv/rakudo,awwaiid/rakudo,tony-o/rakudo,sjn/rakudo,tbrowder/rakudo,Gnouc/rakudo,nbrown/rakudo,softmoth/rakudo,MasterDuke17/rakudo,nbrown/rakudo,awwaiid/rakudo,labster/rakudo,nbrown/rakudo,jonathanstowe/rakudo,jonathanstowe/rakudo,tony-o/rakudo,Gnouc/rakudo,softmoth/rakudo,sjn/rakudo,Gnouc/rakudo,tony-o/rakudo,tony-o/rakudo,samcv/rakudo,rakudo/rakudo,tony-o/rakudo,usev6/rakudo,sjn/rakudo,salortiz/rakudo,Gnouc/rakudo,softmoth/rakudo,nbrown/rakudo,MasterDuke17/rakudo,MasterDuke17/rakudo,awwaiid/rakudo,lucasbuchala/rakudo,MasterDuke17/rakudo,sjn/rakudo,usev6/rakudo,nbrown/rakudo,awwaiid/rakudo,softmoth/rakudo,samcv/rakudo,jonathanstowe/rakudo,MasterDuke17/rakudo,rakudo/rakudo,rakudo/rakudo,samcv/rakudo,usev6/rakudo,salortiz/rakudo,raydiak/rakudo,labster/rakudo,tbrowder/rakudo,Gnouc/rakudo,MasterDuke17/rakudo,rakudo/rakudo