Remove target=_blank links from TinyMCE MathSlate plugin

Bug 1558361

behatnotneeded

Change-Id: I4bebbcca92bd9cbd594ca7d8d83030f6f3e0388b

htdocs/js/tinymce/plugins/mathslate/README.Mahara

@@ -8,3 +8,4 @@ Changes:
 
  * Adjusting the config.json options for uppercase Greek letters
  * Adding the 'aria-hidden="true"' to presentation icons
+ * Removed target=_blank links

htdocs/js/tinymce/plugins/mathslate/help.html

@@ -9,4 +9,4 @@
 
 <p>There is a row of buttons in the center of the editor that allows the user to delete a selection or the whole content, undo the previous action, and redo previously undone actions.
 
-<p><a href="http://docs.moodle.org/26/en/TinyMCE_Mathslate" target="_blank">more information</a>
+<p><a href="http://docs.moodle.org/26/en/TinyMCE_Mathslate">more information</a>

htdocs/js/tinymce/plugins/mathslate/strings.js

@@ -17,7 +17,7 @@ M.util.get_string = function (term, pkg) {
     string['requiretex_desc'] = 'If enabled the Mathslate button is visible only when the TeX filter is enabled in the editor context. Disable if you want it to appear globally (normal if MathJax is included in header sitewide).';
     string['mathjaxurl'] = 'MathJax url';
     string['mathjaxurl_desc'] = 'The url for the MathJax.js file that mathslate should load if MathJax is not already present and configured (probably true if you are using the Moodle TeX filter). The default downloads from the internet using http. If your site uses https use "https://c328740.ssl.cf1.rackcdn.com/mathjax/latest/MathJax.js" or better install a local copy.';
-    string['nomathjax'] = '<p>MathJax does not seem to be present on this site. In order to use this plugin MathJax needs to be configured. MathJax is an opensource software library that is capable of displaying mathmatics in any javascript enabled browser.  Mathslate uses it to render mathematics within the editor. Therefore you should check with the system administrator of this site to see whether MathJax may be installed. See <a href="http://mathjax.org" target="_blank">mathjax.org</a> for more instructions.</p>';
+    string['nomathjax'] = '<p>MathJax does not seem to be present on this site. In order to use this plugin MathJax needs to be configured. MathJax is an opensource software library that is capable of displaying mathmatics in any javascript enabled browser.  Mathslate uses it to render mathematics within the editor. Therefore you should check with the system administrator of this site to see whether MathJax may be installed. See <a href="http://mathjax.org">mathjax.org</a> for more instructions.</p>';
     string['mathslate:desc'] = 'Insert equation';
     
     return string[term];