Merge branch 'kapl_documentation' into 'master'

gh pr 122 + some outstanding commits from GitHub

See merge request qs/ore!41

Author: pcaspers

.gitmodules

@@ -1,5 +1,5 @@
 [submodule "QuantLib"]
 	path = QuantLib
-	url = git@gitlab.acadiasoft.net:qs/quantlib.git
+	url = https://github.com/OpenSourceRisk/QuantLib.git
 	branch = master
 	ignore = dirty

Docs/UserGuide/userguide.tex

@@ -806,8 +806,8 @@ \subsection{Building ORE-SWIG}\label{sec:oreswig}
 \medskip
 To build the wrappers on Windows, Linux, mac OS
 \begin{enumerate}
-\item build ORE and QuantLib first, as shown in the previous section
-\item check out the ORE-SWIG repository into a project directory {\tt oreswig}, change into that directory
+\item build ORE and QuantLib first, as shown in the previous section. It is strongly advised to switch the codebase to a release tag here (e.g. 1.8.7.0), as the versions of the master branch are not always aligned!
+\item check out the ORE-SWIG repository into a project directory {\tt oreswig}, change into that directory (the same advice as above applies here as well, switch to the same release tag as ORE)
 \item pull in the QuantLib-SWIG project by running \\
 {\tt git submodule init} \\
 {\tt git submodule update}

QuantExt/qle/termstructures/strippedcpivolatilitystructure.hpp

@@ -162,7 +162,7 @@ template <class Interpolator2D> void StrippedCPIVolatilitySurface<Interpolator2D
             Rate I1 = ZeroInflation::cpiFixing(index_, maturityDate, observationLag(), indexIsInterpolated());
 
             Time timeToMaturity = dayCounter().yearFraction(underlyingBaseDate, fixDate);
-            QuantLib::Real atmRate = pow(I1 / baseCPI, 1 / timeToMaturity) - 1.0;
+            QuantLib::Real atmRate = std::pow(I1 / baseCPI, 1 / timeToMaturity) - 1.0;
 
             bool useFloor = chooseFloor(strikes_[i], atmRate);