Log Message:
py-hy: updated to 0.13.0

Changes 0.13.1:

[ Language Changes ]
* Pythons 2.6, 3.0, 3.1, and 3.2 are no longer supported
* let has been removed. Python's scoping rules do not make a proper
  implementation of it possible. Use setv instead.
* lambda has been removed, but fn now does exactly what lambda did
* defreader has been renamed to defsharp; what were previously called
  "reader macros", which were never true reader macros, are now called
  "sharp macros"
* try now enforces the usual Python order for its elements (else must
  follow all excepts, and finally must come last). This is only a
  syntactic change; the elements were already run in Python order even when
  defined out of order.
* try now requires an except or finally clause, as in Python
* Importing or executing a Hy file automatically byte-compiles it, or loads
  a byte-compiled version if it exists and is up to date. This brings big
  speed boosts, even for one-liners, because Hy no longer needs to recompile
  its standard library for every startup.
* Added bytestring literals, which create bytes objects under Python 3
  and str objects under Python 2
* Commas and underscores are allowed in numeric literals
* Many more operators (e.g., **, //, not, in) can be used
  as first-class functions
* The semantics of binary operators when applied to fewer or more
  than two arguments have been made more logical
* (** a b c d) is now equivalent to (** a (** b (** c d))),
  not (** (** (** a b) c) d)
* setv always returns None
* When a try form executes an else clause, the return value for the
  try form is taken from else instead of the try body. For example,
  (try 1 (except [ValueError] 2) (else 3)) returns 3.
* xor: If exactly one argument is true, return it
* hy.core.reserved is now hy.extra.reserved
* cond now supports single argument branches

[ Bug Fixes ]
* All shadowed operators have the same arities as real operators
* Shadowed comparison operators now use and instead of &
  for chained comparisons
* partition no longer prematurely exhausts input iterators
* read and read-str no longer raise an error when the input
  parses to a false value (e.g., the empty string)
* A yield inside of a with statement will properly suppress implicit
  returns
* setv no longer unnecessarily tries to get attributes
* loop no longer replaces string literals equal to "recur"
* The REPL now prints the correct value of do and try forms
* Fixed a crash when tokenizing a single quote followed by whitespace

[ Misc. Improvements ]
* New contrib module hy-repr
* Added a command-line option --repl-output-fn