Nuance errors for zero-led literals

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The message should specify "decimal integer literals" instead of "integral values." Hex literals often have leading zeros: 0x00FF. Unexpectedly, hex literals are accepted with no leading digits at all:

scala> 0x
res13: Int = 0

Or should one say, "unhexpectedly."

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Imported From: https://issues.scala-lang.org/browse/SI-9015?orig=1
Reporter: @som-snytt
Affected Versions: 2.11.4

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@soc said:
I would be in favor of deprecating this. One less weird thing people new to the language can trip over.

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@som-snytt said:
Instead of "leading zero is not allowed," it should say, "misleading zero is not allowed."

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@som-snytt said:
scala/scala#4182

Quick, before Jira reconfigures itself to defeat our shield modulation!