add @davidercruz as author and small fixes

_posts/2020-03-06-on-the-fly-transformations.md

@@ -42,7 +42,7 @@ shine is coupling it to a visualization widget such as
 Now it's time to learn how to use the trajectory transformations in MDAnalysis. During the
 following steps, we will apply some transformations on a 1 ns trajectory of a simple
 19-residue peptide embeded in a 128-DMPC membrane, showing the
-[Gromacs](https://www.gromacs.org) `trjconv` command and the equivalent MDAnalysis code
+[Gromacs](http://www.gromacs.org) `trjconv` command and the equivalent MDAnalysis code
 and output. To keep things lightweight, frames are were taken every 100 ps, and water
 molecules were removed. This can be easily done with MDAnalysis.
 
@@ -143,9 +143,8 @@ and rotations of the molecule, allowing us to have a better look at the structur
 our simulations.
 If we want to do this using `trjconv` we would do have to do this in two steps:
 
-     gmx trjconv -f pept_in_memb.xtc -s pept_in_memb.tpr -pbc mol -center -o midstep.xtc
-
-     gmx trjconv -f midstep.xtc -s pept_in_memb.tpr -fit rot+trans -o output.xtc
+    gmx trjconv -f pept_in_memb.xtc -s pept_in_memb.tpr -pbc mol -center -o midstep.xtc
+    gmx trjconv -f midstep.xtc -s pept_in_memb.tpr -fit rot+trans -o output.xtc
 
 And we choose `Protein` as the group to be centered and for the least squares fitting.
 
@@ -220,14 +219,14 @@ it becomes particularly useful when observing protein insertion.
 The beauty of MDAnalysis transformations is the ability to easily create custom transformations.
 All transformations must have the following structure:
 
-```Python
+```python
 def custom_transform(args): # arguments at this point are not mandatory
     #do some things
 
     def wrapped(ts): 
-        # this wrapped function must only take a Timestep as argument
-        # this is where the actual changes to the timestep must be done
-            
+        # This wrapped function must only take a Timestep as argument
+        # and perform the actual changes to the timestep
+
         return ts
 
     return wrapped
@@ -315,9 +314,12 @@ nv.show_mdanalysis(u)
 The two examples of custom transformations shown here are very simple. But 
 more complex things can be done, and we encourage you to try them!
 
-This has been a quick demonstration on the power of the new on-the-fly transformations
-of MDAnalysis. There are more transformations available for you to explore and a whole
-lot more for you to create for your own molecular system. More information on trajectory
-transformations can be found in the [online docs of MDAnalysis](https://www.mdanalysis.org/mdanalysis).
-nv.show_mdanalysis(u)
-```
+This has been a quick demonstration on the power of the new on-the-fly transformations of
+MDAnalysis. There are more transformations available for you to explore and a whole lot
+more for you to create for your own molecular system. More [information on trajectory
+transformations]({{ site.docs.mdanalysis.url
+}}/documentation_pages/trajectory_transformations.html) can be found in the online docs of
+MDAnalysis .
+
+
+— @davidercruz