Add a few missing features that aren't in any documentation.

Testing : precheckin --full --strict-errors
Reviewer: Fare (please)

JTB impact: No
Ops impact: No

Change to config                        : No
Change to XML schema                    : No
Change to DB schema                     : No
Change to transport (timeouts, headers) : No
Any change (or new use) of OAQs         : No
Change to inter-component transactions  : No
Depends on any other checkin / bug      : No

Tests that will verify:

I extended the CL-Protobufs examples

Description:

Add a few missing features that aren't in any documentation.

String literals can look like "foo"<whitespace>"bar".
 - Fix 'parse-string' to handle this.

Option values can be complex structures, not just atoms.
 - If 'parse-proto-option' sees a '{' character after the '=',
   it should use 'parse-text-format' to read the option value.
 - Fix the 'protobuf-option' printer to call 'print-text-format'
   for complex option values.
 - Minor refactoring to the text format parser and printer in
   order to support the above.



git-svn-id: http://svn.internal.itasoftware.com/svn/ita/trunk/qres/lisp/libs/cl-protobufs@560639 f8382938-511b-0410-9cdd-bb47b084005c