Add two more procedures defined in 6.3.6  Vectors.

library procedure:  (vector->list vector)
library procedure:  (list->vector list)

http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-9.html#%_sec_6.3.6
Add procedures defined in 6.3.3  Symbols.

procedure:  (symbol? obj)
procedure:  (symbol->string symbol)
procedure:  (string->symbol string)

http://www.schemers.org/Documents/Standards/R5RS/HTML/r5rs-Z-H-2.html#%_toc_%_sec_6.3.3
Fail to parse #t and #f.

Fix a regression introduced in 8053aa0e1b4fc9f325215724ae9892836b81cdbf.
There is an ambiguity in parsing between boolean objects (#t, #f) and vectors.
Extract parseBool from parseAtom and use try combinator.

Also change the parsing rule to recognize #T and #F too.