fixed some typos reported by William Newman

doc/basics.tex

@@ -176,7 +176,7 @@ image, after which it continues rendering. This can sometimes be useful to
 check if everything is working correctly.
 
 \subsubsection{Rendering an animation}
-The command line interface is ideally suited for rendering large amounts of files in batch
+The command line interface is ideally suited for rendering numbers of files in batch
 operation. You can simply pass in the files using a wildcard in the filename.
 
 If you've already rendered a subset of the frames and you only want to complete the remainder,

src/shapes/heightfield.cpp

@@ -79,7 +79,7 @@ namespace {
  *        \default{none, i.e. object space $=$ world space}
  *     }
  *     \parameter{width, height}{\Integer}{
- *       When the nexted texture is procedural (see below),
+ *       When the nested texture is procedural (see below),
  *       this parameter specifies the resolution at which it should
  *       be rasterized to create a height field made of bilinear patches.
  *	   }

src/subsurface/dipole.cpp

@@ -179,7 +179,7 @@ static int irrOctreeIndex = 0;
  * using a fast hierarchical technique proposed by Jensen and Buhler \cite{Jensen2005Rapid}.
  *
  * There are two different ways of configuring the medium properties.
- * the medium properties.  One possibility is to load a material preset
+ * One possibility is to load a material preset
  * using the \code{material} parameter---see \tblref{medium-coefficients}
  * for details. Alternatively, when specifying parameters by hand, they
  * can either be provided using the scattering and absorption coefficients,