LCov Reporter's strict dependence on a coverage tool

[ManasJayanth]

mocha-lcov-reporter strictly depends on a cover tool and hence fallback to empty object here must be avoided.

 var cov = g._$jscoverage || {};

When invoked without a coverage tool, it must warn.

[StevenLooman]

Thank you for this issue. This is helpful when no output is given, perhaps the cause of #14.

[mathiasrw]

+1

[StevenLooman]

Just released mocha-lcov-reporter 1.2.0

[ManasJayanth]

Awesome! Thanks @StevenLooman