V1.3.0.0rc2 fixes: zlib dependency for SAMtools/Cufflinks/Tophat

`zlib` needs to be listed as an explicit dependency for `Cufflinks` and `Tophat` now, because SAMtools links against the `libz` library provided by the `zlib` module

This will add `-L$EBROOTZLIB` to `$LDFLAGS` for the Cufflinks/Tophat builds too, which fixes linking issues like `undefined reference to `gzopen64'`.

This patch also includes `zlib` as dependency for `SAMtools` with `goolf`, because it should be and already is for the `goalf` and `ictce` easyconfigs.