fix gmp link

.travis/build-linux-wheels.sh

@@ -7,7 +7,7 @@ set -x
 yum install -y pkg-config libffi libffi-devel
 
 # Use updated GMP
-wget -q https://gmplib.org/download/gmp/gmp-6.1.2.tar.bz2 && tar -xjpf gmp-*.tar.bz2 && cd gmp* && ./configure --build=${BUILD_GMP_CPU}-pc-linux-gnu > /dev/null && make > /dev/null && make check > /dev/null && make install > /dev/null && cd ..
+wget -q https://ftp.gnu.org/gnu/gmp/gmp-6.1.2.tar.bz2 && tar -xjpf gmp-*.tar.bz2 && cd gmp* && ./configure --build=${BUILD_GMP_CPU}-pc-linux-gnu > /dev/null && make > /dev/null && make check > /dev/null && make install > /dev/null && cd ..
 
 # Compile wheels
 for PYBIN in /opt/python/*/bin; do

setup.py

@@ -265,7 +265,7 @@ else:
 
 setup(
     name='coincurve',
-    version='4.5.0',
+    version='4.5.1',
 
     description='Cross-platform Python CFFI bindings for libsecp256k1',
     long_description=open('README.rst', 'r').read(),