Remove dependency on seq

[ROCKTAKEY]

I add (require 'seq), since seq-every-p is not autoloaded.
When it is installed by package.el, its absence causes byte-compile warning:

In end of data:
clojure-mode.el:3019:1:Warning: the function ‘seq-every-p’ is not known to be
    defined.

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Thanks!

[bbatsov]

Good catch. Alternatively we can just replace this with something from cl-lib to avoid loading the whole library for a single function.

[ROCKTAKEY]

seq-every-p seems to be replaced with cl-every. Is it better?

[bbatsov]

Yeah, I think that'd be a better solution for this particular problem.

[ROCKTAKEY]

OK, I will fix it.

[ROCKTAKEY]

Fixed.

[bbatsov]

Thanks!