Reject invalid access modifiers

[turbolent]

Closes dapperlabs/cadence-private-issues#16

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit b180983
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Results

	old.txt	new.txt
	time/op		delta
RuntimeFungibleTokenTransfer-2	1.88ms ±23%	1.76ms ±24%	~	(p=0.259 n=7+7)
RuntimeResourceDictionaryValues-2	20.6ms ± 4%	20.9ms ± 4%	~	(p=0.383 n=7+7)
ParseInfix-2	14.6µs ± 8%	14.3µs ± 1%	~	(p=0.432 n=7+5)
ParseArray-2	18.9ms ± 3%	18.7ms ± 5%	~	(p=0.534 n=6+7)
ParseDeploy/byte_array-2	29.7ms ± 2%	29.0ms ± 5%	~	(p=0.181 n=6+7)
ParseDeploy/decode_hex-2	1.67ms ± 4%	1.70ms ± 5%	~	(p=0.456 n=7+7)
QualifiedIdentifierCreation/One_level-2	3.93ns ± 3%	3.95ns ± 3%	~	(p=0.731 n=6+7)
QualifiedIdentifierCreation/Three_levels-2	202ns ± 4%	205ns ± 3%	~	(p=0.132 n=6+6)
ContractInterfaceFungibleToken-2	62.3µs ± 4%	61.9µs ± 3%	~	(p=0.445 n=6+7)
CheckContractInterfaceFungibleTokenConformance-2	228µs ±15%	216µs ± 4%	~	(p=0.165 n=7+7)
NewInterpreter/new_interpreter-2	1.51µs ± 3%	1.54µs ± 7%	~	(p=0.534 n=6+7)
NewInterpreter/new_sub-interpreter-2	3.02µs ± 3%	3.02µs ± 8%	~	(p=0.534 n=6+7)
InterpretRecursionFib-2	3.42ms ± 3%	3.45ms ± 3%	~	(p=0.445 n=6+7)
ParseFungibleToken-2	292µs ± 5%	281µs ± 5%	−3.90%	(p=0.038 n=7+7)
	alloc/op		delta
RuntimeFungibleTokenTransfer-2	273kB ± 0%	273kB ± 0%	~	(p=1.000 n=7+7)
RuntimeResourceDictionaryValues-2	4.05MB ± 0%	4.05MB ± 0%	~	(p=0.902 n=7+7)
QualifiedIdentifierCreation/One_level-2	0.00B	0.00B	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	64.0B ± 0%	64.0B ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	26.5kB ± 0%	26.5kB ± 0%	~	(p=1.000 n=7+7)
CheckContractInterfaceFungibleTokenConformance-2	65.7kB ± 0%	65.7kB ± 0%	~	(p=1.000 n=7+7)
NewInterpreter/new_interpreter-2	720B ± 0%	720B ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	1.18kB ± 0%	1.18kB ± 0%	~	(all equal)
InterpretRecursionFib-2	1.24MB ± 0%	1.24MB ± 0%	~	(p=0.706 n=7+7)
	allocs/op		delta
RuntimeFungibleTokenTransfer-2	4.54k ± 0%	4.54k ± 0%	~	(p=1.000 n=7+7)
RuntimeResourceDictionaryValues-2	102k ± 0%	102k ± 0%	~	(p=0.085 n=6+7)
QualifiedIdentifierCreation/One_level-2	0.00	0.00	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	2.00 ± 0%	2.00 ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	457 ± 0%	457 ± 0%	~	(all equal)
CheckContractInterfaceFungibleTokenConformance-2	1.07k ± 0%	1.07k ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	11.0 ± 0%	11.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	36.0 ± 0%	36.0 ± 0%	~	(all equal)
InterpretRecursionFib-2	25.0k ± 0%	25.0k ± 0%	~	(all equal)