bump libzmq version in travis config

this will solve a dpkg error:
The following extra packages will be installed:
  libzmq1
The following NEW packages will be installed:
  libzmq-dev libzmq1
0 upgraded, 2 newly installed, 0 to remove and 95 not upgraded.
Need to get 432 kB of archives.
After this operation, 1,458 kB of additional disk space will be used.
Get:1 http://ppa.launchpad.net/travis-ci/zero-mq/ubuntu/ precise/main
libzmq1 amd64 3.2.2-0~travis1 [134 kB]
Get:2 http://ppa.launchpad.net/travis-ci/zero-mq/ubuntu/ precise/main
libzmq-dev amd64 3.2.2-0~travis1 [298 kB]
Fetched 432 kB in 0s (556 kB/s)
Selecting previously unselected package libzmq1.
(Reading database ... 71915 files and directories currently installed.)
Unpacking libzmq1 (from .../libzmq1_3.2.2-0~travis1_amd64.deb) ...
dpkg: error processing
/var/cache/apt/archives/libzmq1_3.2.2-0~travis1_amd64.deb (--unpack):
 trying to overwrite '/usr/lib/x86_64-linux-gnu/libzmq.so.3.0.0', which
is also in package libzmq3 3.2.2+dfsg-1~travis1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Selecting previously unselected package libzmq-dev.
Unpacking libzmq-dev (from .../libzmq-dev_3.2.2-0~travis1_amd64.deb) ...
Processing triggers for man-db ...
Errors were encountered while processing:
 /var/cache/apt/archives/libzmq1_3.2.2-0~travis1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
The command "sudo apt-get install libzmq-dev" failed and exited with 100
during before_install.