Fix MemoryStorage & WebStorage primary key support

[panarch]

depends on #1114

Fix MemoryStorage primary key support - replace IndexMap to BTreeMap for storing rows.
Fix WebStorage primary key support - sort on scan_data if primary key exists in the schema.
Update test-suite/ primary_key to test edge cases.

[coveralls]

Pull Request Test Coverage Report for Build 4335920034

• 11 of 11 (100.0%) changed or added relevant lines in 2 files are covered.
• 46 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.1%) to 98.734%

---

Files with Coverage Reduction	New Missed Lines	%
core/src/executor/validate.rs	1	99.24%
test-suite/src/tester/mod.rs	19	87.33%
core/src/executor/aggregate/mod.rs	26	86.6%

Totals
Change from base Build 4335910391:	-0.1%
Covered Lines:	40322
Relevant Lines:	40839

---

💛 - Coveralls