Add submit buttons to some forms

app/partials/views/modules/forgot-form.jade

@@ -9,3 +9,4 @@ div.forgot-form-container(tg-forgot-Password)
                   placeholder="Username or email")
         fieldset
             a.button.button-forgot.button-gray(href="", title="Reset Password") Reset Password
+            input(type="submit", style="display:none")

app/partials/views/modules/invitation-login-form.jade

@@ -6,3 +6,4 @@ form.login-form
         a.forgot-pass(href="", tg-nav="forgot-password", title="Did you forgot your password?") Forgot it?
     fieldset
         a.button.button-login.button-gray(href="", title="Log in") Enter
+        input(type="submit", style="display:none")

app/partials/views/modules/invitation-register-form.jade

@@ -7,6 +7,7 @@ form.register-form
         input(type="password"  placeholder="Set a password", data-required="true")
     fieldset
         a.button.button-register.button-gray(href="", title="Sign up") Sign up
+        input(type="submit", style="display:none")
 
     p.register-text
         // TODO