Fix big-endian build and add CI tests for it.

[michaelwoerister]

This PR

• fixes a compilation error on big endian platforms
• adds a big endian cargo check build to CI, so we catch compilation errors like these early next time
• bumps the version to 0.7.1 so we can use that to unblock self-profiling: Support recording query keys rust#67397.

This PR should fail until the big endian specific error uncovered here is fixed.

[michaelwoerister]

But it fails before it can even install Rust :(

[wesleywiser]

measureme/measureme/src/raw_event.rs

Lines 152 to 153 in 560162a

	event_kind: StringId::reserved(LittleEndian::read_u32(&bytes[0..])),
	event_id: StringId::reserved(LittleEndian::read_u32(&bytes[4..])),

is cfg'd out on little-endian and got broken in a prior commit. I believe these should just be StringId::new() right?

[michaelwoerister]

Yes, that's the error. I'm tweaking .travis.yml until it properly catches the error and then add a fix to this PR.

[wesleywiser]

Oh, sorry. I didn't realize what was going on. Carry on! 🙂

[michaelwoerister]

Alright, ready for review :)