make BuiltinMap immutable; use builder pattern to avoid double-defensive copying both at Transformer and constructors
addressed issues in code review
isolated the internal state of BuiltinMap.Builder completely from effect of outside change; this also simplifies the code
Merge pull request #537 from yilongli/cleanup-BuiltinMap-api

Cleanup builtin map api
KLabelConstant no longer has TermContext
Made a quick-regression ktest, and added wiring xml

The test is a clone of kool-typed-dynamic:
 - copied the kool-typed-dynamic definition and its programs, inputs, and outputs to /tests/regression/quick
 - adapted its xml
 - /tests/quick.xml is a shortcut wiring
remove term Context caching
clean up imports
remove KLabelConstant dependence on TermContext
Merge pull request #562 from kframework/quick-regression-ktest

Made a quick-regression ktest, and added wiring xml
Merge pull request #563 from kframework/remove-TermContext-caching

Remove term context caching
Merge pull request #564 from kframework/refactor-KLabelConstant

Refactor KLabelConstant