small edits to issue template stanza

Author: eddelbuettel

.github/ISSUE_TEMPLATE.md

@@ -1,25 +1,18 @@
 
 ### Reporting an Issue
 
-_Make use of the *Preview* tab just above!_
+Make use of the *Preview* tab just above!
 
 #### Before filing an issue with Rcpp, please ensure that you
 
-- searched the mailing list archives for the
-  [rcpp-devel](https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel) list for the question I want to
-  ask about; you can do this at at Google with the `site:` qualifier as in this simple example:
-  `site:lists.r-forge.r-project.org rcpp-devel how do I declare a const vector`;
+- searched the mailing list archives for the [rcpp-devel](https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel) list for the question I want to
+  ask about; you can do this at at Google with the `site:` qualifier as in this simple example: `site:lists.r-forge.r-project.org rcpp-devel how do I declare a const vector`;
 
-- searched [StackOverflow](https://stackoverflow.com/) under the `[rcpp]` tag by searching _e.g._ via `[rcpp] how do I sample a vector`;
+- searched the [StackOverflow](https://stackoverflow.com/) `[rcpp]` tag _e.g._ via `[rcpp] how do I sample a vector`;
 
-- searched the existing [GitHub issues](https://github.com/RcppCore/Rcpp/issues) which too can be search among open and
-  (importantly!) closed ones;
+- searched existing [GitHub issues](https://github.com/RcppCore/Rcpp/issues) which can be searched among open and closed ones;
 
-- read the [Contributing](https://github.com/RcppCore/Rcpp/blob/master/Contributing.md) page for details on preferred
-  reporting and style;
+- read the [Contributing](https://github.com/RcppCore/Rcpp/blob/master/Contributing.md) page for details on preferred reporting and style;
 
-#### If you have the above, remove the text above and provide
-
-- A [`Minimally Complete and Reproducible Example`](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example)
-
-- The output of `sessionInfo()` plus relevant information about the C++ compiler used not added by R
+If you have the above, remove the text above and provide a [`Minimally Complete and Reproducible Example`](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example),
+the output of `sessionInfo()` plus relevant information about the C++ compiler.