Add support for greater/less than for isFloat().

[hkwu]

When I was building the project I got diffs in quite a few of the built files for lines like

arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : String(new Date());

Should I commit those as well?

[coveralls]

Coverage remained the same at 99.14% when pulling cb09637 on hkwu:feature/isFloat into 8c59fd1 on chriso:master.

[chriso]

Can you rebase against master?

[coveralls]

Coverage remained the same at 99.14% when pulling 1237c55 on hkwu:feature/isFloat into d4691a6 on chriso:master.

[chriso]

LGTM, thanks!