EUMM compatibility update

[mohawk2]

Current Makefile.PL relies on the EUMM-generated Makefile having no spaces before : in rules. This patch removes that assumption, which is incorrect from EUMM 7.11_02. This addresses:

• this cpantesters failure: http://www.cpantesters.org/cpan/report/ce4cbb5e-917f-11e5-8342-5a9f251cf1b3
• this RT report: https://rt.cpan.org/Ticket/Display.html?id=109962
• this EUMM issue (which tracks blockers for EUMM 7.12): https://github.com/Perl-Toolchain-Gang/ExtUtils-MakeMaker/issues/252

[dk]

Thank you for the report! I'm on vacation from tomorrow, so will look after two weeks.