build: change reduce exports/static libstdc++ options for gitian and travis

For Gitian releases:
  - Windows builds remain unchanged. libstdc++ was already linked statically.
  - OSX builds remain unchanged. libstdc++ is tied to the SDK and not worth
    messing with.
  - Linux builds now statically link libstdc++.

For Travis:
  - Match the previous behavior by adding --enable-reduce-exports as
  necessary.
  - Use static libstdc++ for the full Linux build.

contrib/gitian-descriptors/gitian-linux.yml

@@ -23,7 +23,7 @@ files: []
 script: |
   WRAP_DIR=$HOME/wrapped
   HOSTS="i686-pc-linux-gnu x86_64-unknown-linux-gnu"
-  CONFIGFLAGS="--enable-upnp-default --enable-glibc-back-compat"
+  CONFIGFLAGS="--enable-upnp-default --enable-glibc-back-compat --enable-reduce-exports LDFLAGS=-static-libstdc++"
   FAKETIME_HOST_PROGS=""
   FAKETIME_PROGS="date ar ranlib nm strip"
 

contrib/gitian-descriptors/gitian-osx.yml

@@ -27,7 +27,7 @@ files:
 script: |
   WRAP_DIR=$HOME/wrapped
   HOSTS="x86_64-apple-darwin11"
-  CONFIGFLAGS="--enable-upnp-default GENISOIMAGE=$WRAP_DIR/genisoimage"
+  CONFIGFLAGS="--enable-upnp-default --enable-reduce-exports GENISOIMAGE=$WRAP_DIR/genisoimage"
   FAKETIME_HOST_PROGS=""
   FAKETIME_PROGS="ar ranlib date dmg genisoimage"
 

contrib/gitian-descriptors/gitian-win.yml

@@ -26,7 +26,7 @@ files: []
 script: |
   WRAP_DIR=$HOME/wrapped
   HOSTS="x86_64-w64-mingw32 i686-w64-mingw32"
-  CONFIGFLAGS="--enable-upnp-default"
+  CONFIGFLAGS="--enable-upnp-default --enable-reduce-exports"
   FAKETIME_HOST_PROGS="g++ ar ranlib nm windres strip"
   FAKETIME_PROGS="date makensis zip"