Fixes in doc

Thanks to Qingh Liao

src/colvar/DRMSD.cpp

@@ -45,7 +45,7 @@ often cheaper and easier to calculate the distances between all the pairs of ato
 between the two structures, \f$\mathbf{X}^a\f$ and \f$\mathbf{X}^b\f$ can then be measured as:
 
 \f[
-d(\mathbf{X}^A, \mathbf{X}^B) = \frac{1}{N(N-1)} \sum_{i \ne j} [ d(\mathbf{x}_i^a,\mathbf{x}_j^a) - d(\mathbf{x}_i^b,\mathbf{x}_j^b) ]^2
+d(\mathbf{X}^A, \mathbf{X}^B) = \sqrt{\frac{1}{N(N-1)} \sum_{i \ne j} [ d(\mathbf{x}_i^a,\mathbf{x}_j^a) - d(\mathbf{x}_i^b,\mathbf{x}_j^b) ]^2}
 \f]
 
 where \f$N\f$ is the number of atoms and \f$d(\mathbf{x}_i,\mathbf{x}_j)\f$ represents the distance between

user-doc/tutorials/belfast-7.txt

@@ -22,7 +22,7 @@ In PT, exchanges are usually attempted between adjacent temperatures
 with the following acceptance probability:
 
 \f[
-p(i \rightarrow j) = min \{ 1,\Delta_{i,j}^{PT} \},
+p(i \rightarrow j) = min \{ 1,e^{\Delta_{i,j}^{PT}} \},
 \f]
 
 with