Check foreign_identifier_lookup when inserting with an entity type.

[Anders429]

Fixes #230. See the comments there for explanation.

[codecov]

Codecov Report

Merging #231 (208618b) into dev (d77d140) will increase coverage by 0.04%.
Report is 3 commits behind head on dev.
The diff coverage is 93.47%.

@@            Coverage Diff             @@
##              dev     #231      +/-   ##
==========================================
+ Coverage   97.07%   97.12%   +0.04%     
==========================================
  Files          84       84              
  Lines       14552    14564      +12     
==========================================
+ Hits        14127    14145      +18     
+ Misses        425      419       -6     

Files Changed	Coverage Δ
src/entity/allocator/location.rs	76.92% <0.00%> (+5.49%)	⬆️
src/system/schedule/sendable.rs	66.66% <0.00%> (ø)
src/archetypes/mod.rs	99.17% <96.15%> (-0.01%)	⬇️
src/archetype/identifier/mod.rs	95.01% <100.00%> (-0.08%)	⬇️
src/query/mod.rs	100.00% <100.00%> (ø)
src/world/impl_serde.rs	99.28% <100.00%> (+0.02%)	⬆️

... and 4 files with indirect coverage changes