Bug fixed. In the previous version, all right open macros and all delimited arguments

Bug fixed. In the previous version, all right open macros and all delimited arguments
of a macro, could be closed inserting a closing brace.
Now, a right open macro can be closed only if it's contained in a group (with id).
To close it, the user has to type a closing brace, which closes the group.
A right open macro not contained in a group, cannot be closed: any closing brace
is ignored.
The only way to exit from a delimited argument, the user has to type the delimiter (or the
sequence of delimiters).
To fix this bug, a new method has been added to the TPushParser class. This method
(bool correctBrace(void)), is used to determine if a closing brace is appropriate to
close a right open macro.
In addition, advance method has been modified.