Revert "CLJ-1252 - fix bug in keyword regex that allowed keywords starting with a number"

This reverts commit 39aa021e83b4d5bc2d7c3b13c56c04daee4c27d0.
1.6 changes, courtesy Alex Miller
Fix a bug on persistent maps/sets when conjing on a collision node which underwent a transient modification.

Signed-off-by: Stuart Halloway <stu@thinkrelevance.com>
CLJ-1285: add generative test for conj/disj/persistent/transient on sets

Signed-off-by: Stuart Halloway <stu@thinkrelevance.com>
[maven-release-plugin] prepare release clojure-1.6.0-alpha2
[maven-release-plugin] prepare for next development iteration
disable broken test
Merge remote-tracking branch 'upstream/master'

Conflicts:
	test/clojure/test_clojure/pprint/test_pretty.clj