improve load-file error message
add $PWD to the load-paths by default

this allows loading "project-local" namespaces and files easily.
don't fail when being symlinked to
try finding the binary in $PATH if it isn't in the current directory
don't use load-file for batch mode

it's confusing because it interacts with load-paths in strange ways.
(load-file doesn't simply load a file and evaluates it, but it looks
through load-paths and tries to locate it in there.)
print an error if file isn't present

doesn't work with inaccessible files, though.
All functions extend IFn
renamed extensions to .pxi
Merge pull request #71 from heyLu/load-paths

Improve load path/batch mode
Merge pull request #73 from andrewchambers/pxi

renamed extensions to .pxi
use new extension in examples and benchmarks as well
fix batch mode

in some (most?) cases it didn't read multiple expressions, although it
did read and execute the two print expressions from the previous hello
world example.

doing it this way has the advantage of executing the statements as they
are read.
Merge remote-tracking branch 'upstream/master' into functions
reudce -> reduce
variadic comp
fix get-in behavior
split load-file into load-ns and load-file

load-file now just loads and runs a file at the given path, while
load-ns searches for a file relative to load-paths.
add load-reader
use load-reader in batch mode
Merge pull request #70 from thomasmulvaney/functions

All functions extend IFn