Add types tests.
Fix type bugs with arrays and pointer subtraction
- Remove superfluous Number cast when the right-hand side is already a numeric
- Fix pointer subtraction. Force both operands to have bases of equal size.
- Fix alignment of array types.
Added matrix multiplication test.
More test cases.
tests: Rewrote tests to use assert.js instead of should.js.
Added static struct members.
Fix bug in when computing struct size with member methods.
Migrated test cases to mocha tests.
Added mocha test support.