Bug fix in saving template containing custom_tags_modules feature
Bug fix in saving template containing custom_tags_modules feature

* Bug fix: when compiling templates with custom tags with a given
custom_tags_modules option, the arguments are saved as atoms in the
AST as opposed to strings. This causes a failure when decompiling
the beam and printing its source by erl_prettypr.

In order to illustrate the issue compile the template test.dtl containing:

    {% tr xxx="ABC" %}

with options:

    [
        , {doc_root, "src"}
        , {out_dir,   "ebin"}
        , {compiler_options, [verbose, debug_info, report, return]}
        , {custom_tags_modules, [custom_tags]}
        , {force_recompile, true}
    ].

where custom_tags module is:

    -module(custom_tags).

    -export([tr/2]).

    tr(Vars, Context) ->
        io:format("Vars: ~p\n  Context: ~p\n", [Vars, Context]),
        [].

Observe the return code of erlydtl_compiler:compile/3, and also try to
decompile the emitted beam with:
[http://erlang.org/pipermail/erlang-questions/2006-January/018813.html]

truqu/erlydtl,project-fifo/erlydtl,huangered/erlydtl,truqu/erlydtl,oxpa/erlydtl,huangered/erlydtl,A40in/erlydtl,A40in/erlydtl,kivra/erlydtl,wrw/erlydtl,aerosol/erlydtl,oxpa/erlydtl,oxpa/erlydtl,erlydtl/erlydtl,wrw/erlydtl,erlydtl/erlydtl,aerosol/erlydtl,project-fifo/erlydtl,kivra/erlydtl,huangered/erlydtl,wrw/erlydtl,quasiconvex/erlydtl,quasiconvex/erlydtl,truqu/erlydtl,alexr/erlydtl,aerosol/erlydtl,alexr/erlydtl,A40in/erlydtl,alexr/erlydtl,project-fifo/erlydtl,chaptastic/erlydtl,chaptastic/erlydtl,campanja-forks/erlydtl,chaptastic/erlydtl,campanja-forks/erlydtl,kivra/erlydtl,quasiconvex/erlydtl,campanja-forks/erlydtl,erlydtl/erlydtl