gnu: Add emacs-web-mode.

* gnu/packages/emacs.scm (emacs-web-mode): New variable.

gnu/packages/emacs.scm

@@ -2000,3 +2000,26 @@ (define-public emacs-yaml-mode
 that indentation determines structure, this mode provides indentation and
 indentation command behavior very similar to that of python-mode.")
     (license license:gpl3+)))
+
+(define-public emacs-web-mode
+  (package
+    (name "emacs-web-mode")
+    (version "14")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "https://raw.githubusercontent.com/fxbois"
+                                  "/web-mode/v" version "/web-mode.el"))
+              (file-name (string-append "web-mode-" version ".el"))
+              (sha256
+               (base32
+                "086hik5fmxg3kx74qmransx9cz961qd22d4m6ah2dw6cwaj1s3s5"))))
+    (build-system emacs-build-system)
+    (synopsis "Major mode for editing web templates")
+    (description "Web-mode is an Emacs major mode for editing web templates
+aka HTML files embedding parts (CSS/JavaScript) and blocks (pre rendered by
+client/server side engines).  Web-mode is compatible with many template
+engines: PHP, JSP, ASP, Django, Twig, Jinja, Mustache, ERB, FreeMarker,
+Velocity, Cheetah, Smarty, CTemplate, Mustache, Blade, ErlyDTL, Go Template,
+Dust.js, React/JSX, Angularjs, ejs, etc.")
+    (home-page "http://web-mode.org/")
+    (license license:gpl3+)))