Put ecma parsing test into a zero-separated file

This reduces the size of literal strings which make some compilers whine.

Also enable all tests, including labels and for..in which are now fully implemented
(and were already covered in manual tests).

Now parses 11112 ecma262 tests. The remaining 454 tests are negative tests,
which we should eventually check as well.
Apply cleanups from 675e049ceeb0da9
Implement core of new VM runtime

Property set/get/del, core primitive types and generic object
Merge pull request #73 from cesanta/ecmazero

Put ecma parsing test into a zero-separated file
Merge pull request #74 from cesanta/cleanup

Apply cleanups from 675e049ceeb0da9
Merge pull request #75 from cesanta/runtime

Implement core of new VM runtime
Split pure regex functionality into slre.[ch]
Merge pull request #77 from cesanta/split_headers

Split pure regex functionality into slre.[ch]
Implement a simple AST interpreter

This interpreter traverses the AST and interprets simple statements
and expressions.

Function statements are not yet supported; it can execute a `SCRIPT`
node containing a list of statements. Basic loops, assignments and
binary expressions work. L-value support is limited to simple identifiers.

Array and object literals are supported. A rough attempt at implementing javascript
string<->numeric<->truth conversions has been made here, but with the intention of
showing the general idea of the interpreter rather than attempting to fill in the details.

Variable declaration and scopes are not implemented.

The interpreter uses the old VM runtime functions, and has to be ported to the new
VM definitions when they are ready.