Ensure that "make compile" works around rebar when lfe.config is present

[oubiwann]

This work is required due to the impact of issue #135 and supporting the lfetool download deps command (to override versions pinned in rebar.config files).

[oubiwann]

This is only going to work when projects update their deps to not use explicit app versions.

I.e., from this sort of thing:

{deps, [
    {lfe, "0.9.9", {git, "git://github.com/rvirding/lfe.git", {tag, "v0.9.0"}}},
    {ltest, "0.4.1", {git, "git://github.com/lfex/ltest.git", {tag, "0.4.1"}}}
  ]}.

to this sort of thing:

{deps, [
    {lfe, ".*", {git, "git://github.com/rvirding/lfe.git", {tag, "v0.9.0"}}},
    {ltest, ".*", {git, "git://github.com/lfex/ltest.git", {tag, "0.4.1"}}}
  ]}.

This means that versioning will only be managed by git tags, and not the actual Erlang-defined version number of the app (in the app.src file).

Any project that wants to use lfetool download deps to override their rebar.config will need to make this change before switching to lfetool download deps.

[oubiwann]

• [x] Update lutil deps to remove explicit app version
• [x] Update ltest deps to remove explicit app version
• [x] Update lfest deps to remove explicit app version
• [x] Update exemplar deps to remove explicit app version
• [x] Update project templates in lfetool to remove explicit app version in all rebar.config files

[oubiwann]

Done.