15.5 strings : eliminate unresolved variables and adding information about the exceptions if needed

Two kind of changes.

1) Eliminate unresolved variables. 

Most of the test have in this section have unresolved variables 

I replace "foo = someValue" with "var foo = someValue"


2) Add information about exceptions that were catches silently. 

Some of the catch silently the exceptions without checking that the correct exception was launched

I replace 
try{
...
}catch(e){}

With =>

try{
...
}catch(e){
  if(e typeof SomeError){
     $ERROR(....)
  }
}

[Jasvir, 2010-08-06 18:03:30]

LGTM

[christian.plesner.hansen, 2010-08-08 02:28:10]

LGTM++.  This is really awesome work Pedro.

I do have two comments but they're not serious enough that you have to fix them
before submitting.

In the cases where you've changed

try {
  __instance = ...
  ...
}

to

try {
  var __instance = ...
  ...
}

theres some inconsistency in whether you've updated the $FAIL as well, sometimes
you add 'var' there too and sometimes you don't.

Also, there's a tiny bit of inconsistency wrt. spacing in how you've added 'var'
to 'for' loops, sometimes you've changed

for ( k = ...; ... )

into

for ( var k = ...; ... )

and sometimes into

for (var k = ...; ... )

If there was more time I'd have suggested you make those consistent but at this
point I'm fine with submitting it as it is.