PHPC-714: BSON corpus tests

[jmikola]

https://jira.mongodb.org/browse/PHPC-714

Also, various corpus test cases currently fail. This is likely due to libbson, so we may want to hold off until the C driver implements these tests. I expect that at least some issues cannot be resolved without breaking BC.

[derickr]

So is this still WIP?

[jmikola]

So is this still WIP?

Changed it to WIP. I need to group the specific failures so we can relay those to the C driver team and then update the tests to XFAIL.

[jmikola]

A few XFAIL markers depend on other pull requests:

• PHPC-884: Do not skip public property with empty string name during BSON encoding #504
• PHPC-883: BSON array keys should be disregarded during visitation #505
• PHPC-885: Alphabetize Regex flags when instantiating from BSON #506

Some markers depend on unresolved libbson issues, some of which should be addressed in 1.6.0 (see also: CDRIVER-1947).

Lastly, this PR currently only implements the "valid" test cases. I still need to handle the "decodeErrors" tests.

[jmikola]

The "decodeErrors" and "parseErrors" tests are now handled by the conversion script and included in the PR, so I'm removing the WIP label.

[derickr]

Looks reasonable, but I didn't check all 870 tests...

[jmikola]

Rebased with updated XFAIL blocks for other resolved tickets. We may want to hold off on merging this until libbson 1.6.0 is tagged (likely PHPC 1.3.0).

[jmikola]

I moved the libbson 1.6.0 upgrade to its own PR (#511) and added XFAIL blocks to BSON corpus tests that still fail in 1.5.x. This will allow us to merge the corpus tests in our 1.2.x branch.