Move templates outside the source .mk filestemplates

Templates now no longer use Make variables for substitution
but instead replace strings with their equivalent:

  template_name: Corresponds to n=template_name
  project_name:  Corresponds to $(PROJECT) or in=project_name

This allows defining templates outside of Makefiles. For
example an external plugin could define their templates
in templates/my_template.erl and then have the following
in the included Makefile:

  tpl_my_template = $(file < $(THIS)/templates/my_template.erl)

By default the created file will be in src/template_name.erl.
This can be overriden with the tplp_* variable:

  tplp_my_template = src/model/my_template.erl

Substitution is applied both to the template contents and
to its path.

In addition, attempting to overwrite an existing file when
creating a template will result in failure.

1 files changed, 10 insertions, 0 deletions

diff --git a/templates/apps_Makefile b/templates/apps_Makefile
new file mode 100644
index 0000000..093287f
--- /dev/null
+++ b/templates/apps_Makefile
@@ -0,0 +1,10 @@
+PROJECT = project_name
+PROJECT_DESCRIPTION = New project
+PROJECT_VERSION = 0.1.0
+template_sp
+# Make sure we know where the applications are located.
+ROOT_DIR ?= rel_root_dir
+APPS_DIR ?= ..
+DEPS_DIR ?= rel_deps_dir
+
+include rel_root_dir/erlang.mk