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Fix GetClojureIndent() undesireable cursor move.
Eliminate cursor side-effect in GetClojureIndent().
Merge branch 'no-cursor-move-during-indentexpr'

While an indentexpr is allowed to move the cursor while calculating a
line's indent, doing so makes GetClojureIndent() unusable as a library
function. Paredit.vim, for instance, makes use of this function.

Closes #49

* no-cursor-move-during-indentexpr:
  Eliminate cursor side-effect in GetClojureIndent().
  Fix GetClojureIndent() undesireable cursor move.
Fix indentexpr cursor restoration and add a test case