Add a QuicConfig to squic Dial/Listen methods

[chaehni]

This PR enables clients to pass a QuicConfig to Dial/Listen methods in the squic package.

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This change is 

[lukedirtwalker]

Reviewed 2 of 2 files at r1.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @chaehni)

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go/lib/snet/squic/squic.go, line 76 at r1 (raw file):

func ListenSCIONWithBindSVC(network *snet.SCIONNetwork, laddr, baddr *snet.Addr,
	svc addr.HostSVC, quicConfig *quic.Config) (quic.Listener, error) {
	if len(srvTlsCfg.Certificates) == 0 {

Please leave a blank line after 2 lined function declarations (see https://github.com/scionproto/scion/wiki/Coding-Guidelines#function-declaration-over-multiple-lines), also in the other methods in this file. Some of them were actually wrong before, It would be great if you could change those as well. Thanks.

[chaehni]

Adapted the formatting according to the guidelines.

Reviewable status: 1 of 2 files reviewed, 1 unresolved discussion (waiting on @lukedirtwalker)

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go/lib/snet/squic/squic.go, line 76 at r1 (raw file):

Previously, lukedirtwalker (Lukas Vogel) wrote…

Please leave a blank line after 2 lined function declarations (see https://github.com/scionproto/scion/wiki/Coding-Guidelines#function-declaration-over-multiple-lines), also in the other methods in this file. Some of them were actually wrong before, It would be great if you could change those as well. Thanks.

Done.

[kormat]

Reviewed 1 of 2 files at r1, 1 of 1 files at r2.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @lukedirtwalker)

[kormat]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @lukedirtwalker)

[lukedirtwalker]

Reviewable status: complete! all files reviewed, all discussions resolved

[lukedirtwalker]

Reviewed 1 of 1 files at r3.
Reviewable status: complete! all files reviewed, all discussions resolved