Updated the _VERSION to the proper version.
Make setfenv more closely match 5.1's behavior

According to http://www.lua.org/manual/5.1/manual.html#pdf-setfenv:

* "setfenv returns the given function"
* "when f is 0 setfenv changes the environment of the running thread. In
  this case, setfenv returns no values"
Make getfenv more closely match 5.1's behavior

According to http://www.lua.org/manual/5.1/manual.html#pdf-getfenv "The
default for f is 1" so when there is no argument passed, we should be
passing 1 into debug.getinfo. Without this, Lua complains about the
"attempt to perform arithmetic on local 'f' (a nil value)".  Hence f
should be initialized to 0 when no argument is passed.
Merge pull request #23 from norman/get_set_env_fixes

(g|s)etfenv fixes
5.2 compatibility: unpack is used in several places; utils ensures that it is always defined
ISO 8601 seconds, minutes and hours start at _zero_! stringio was skipping empty lines and not handling fractional numbers properly; now supports Lua 5.2 behaviour
ISO 8601 UTC dates handled better (I think)
pretty.load is documented, and has paranoid mode. pretty.read can no longer crash and has closed the string-method vunerability
utils.lua51 is now defined; missing unpack or loadstring for 5.2 has been sorted
Lua 5.2 compatibility
lua/pl/Date.lua
typo broke Date tests - dammit
lua51 broken for compat-mode lua52
Merge branch 'master' of github.com:stevedonovan/Penlight
Set equality not defined; tostring borked, and Map's metatable trashed
issue 26: lapp was converting numbers in names to underscores
tablex.range crash fix. Now range(10,10)=={10} and range(10,9) == {}
issue 19: keys which are not numbers or strings caused pretty.write to crash
path.join takes an arbitrary number of paths
bumped version up to 1.0.2