GAP.jl 0.7.7 released

Today GAP.jl 0.7.7 has been released.

Diff since v0.7.6

Closed issues:

• GAP.jl not loading on recent master version of julia (#783)

Merged pull requests:

• Add quiet kwarg to Packages.load (#781) (@fingolfin)
• Replace some calls to low-level GAP functions (#782) (@fingolfin)
• Fix compatibility with Julia nightly (#784) (@fingolfin)