doc: README.md should mention lua 5.1 as build req
build: wreck needs $(LUA_INCLUDE) on ubuntu

On ubuntu, liblua5.1-0-dev packages lua.h in /usr/include/lua5.1
build: wrexecd needs $(LIBPTHREAD) on ubuntu

We get undefined pthread_mutex_trylock() at link time on ubuntu
when linking wrexecd without -lpthread
flux-start: include <sys/resource.h> for ubuntu
doc: README.md should mention asciidoc
test: get spellcheck working with newer automake

Putting a command in TEST_ENVIRONMENT and expecting it
to iterate over a list of arguments in TEST is fragile.
In newer automakes, other things are appended to TEST_ENVIRONMENT
and this breaks.

Modify the man page spell checker so that it is one test
called 'spellcheck' that checks all the *.[1-9] files it can glob.
test: add some words to dict for ubuntu

Apparently these words were in our dictionary for rhel6 but
not on ubuntu.
build: link libcore against $(LIBDL) for ubuntu
build: add LIBUTIL to lua binding for ubuntu

Without this forkpty() comes up undefined
Merge pull request #6 from garlick/ubuntu-fixes

Various minor fixes when building on ubuntu 14.04.1 LTS Trusty Tahr