[libsigc++2] Fix some typos

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 4811678630068ec56a338ebc97f1f83a13a4d807
Author: Kjell Ahlstedt <kjell ahlstedt bredband net>
Date:   Sun Dec 13 19:31:27 2015 +0100

    Fix some typos

 build/cxx.m4      |    2 +-
 sigc++config.h.in |    4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/build/cxx.m4 b/build/cxx.m4
index c055faa..7e92820 100644
--- a/build/cxx.m4
+++ b/build/cxx.m4
@@ -111,7 +111,7 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
 [
   sigcm_cxx_self_reference_in_member_initialization=yes
   AC_DEFINE([SIGC_SELF_REFERENCE_IN_MEMBER_INITIALIZATION],[1],
-            [does c++ compiler allows usage of member function in initialization of static member field.])
+            [does the C++ compiler allow usage of member function in initialization of static member field.])
 ],[
   sigcm_cxx_self_reference_in_member_initialization=no
 ])
diff --git a/sigc++config.h.in b/sigc++config.h.in
index 3311216..d9627a8 100644
--- a/sigc++config.h.in
+++ b/sigc++config.h.in
@@ -32,7 +32,7 @@
 #ifdef SIGC_MSC
 /*
  * MS VC7 Warning 4251 says that the classes to any member objects in an
- * exported class must be also be exported.  Some of the libsigc++
+ * exported class must also be exported.  Some of the libsigc++
  * template classes contain std::list members.  MS KB article 168958 says
  * that it's not possible to export a std::list instantiation due to some
  * wacky class nesting issues, so our only options are to ignore the
@@ -69,7 +69,7 @@
    calling operator() template methods omitting the template keyword. */
 # undef SIGC_MSVC_TEMPLATE_SPECIALIZATION_OPERATOR_OVERLOAD
 
-/* does c++ compiler allows usage of member function in initialization of
+/* does the C++ compiler allow usage of member function in initialization of
    static member field. */
 # undef SIGC_SELF_REFERENCE_IN_MEMBER_INITIALIZATION