Compatible with single letter camel naming

[wangruochan]

There are many Single-Letter-Camel Naming in OpenSource project, etc:HBase,XStream,BTrace,TEngine.

My commit modified the regex so that classnames can be named starting with any single capital letter

[githubsoftware2015]

A problem occurred configuring project ':p3c-common'.

Could not resolve all files for configuration ':p3c-common:detachedConfiguration1'.
Could not download ideaIC.zip (com.jetbrains.intellij.idea:ideaIC:145.258.11)
> Could not get resource 'https://cache-redirector.jetbrains.com/www.jetbrains.com/intellij-repository/releases/com/jetbrains/intellij/idea/ideaIC/145.258.11/ideaIC-145.258.11.zip'.
> Read timed out
您好，这个应该怎么解决呢

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[XenoAmess]

In short I disagree this pr.
IMO we shall think it deeper.
two reasons.
1.
The 'I' in original regex means Interface, which do have a special meaning.
There are actually basically two flows of programmers, one of them would like to name an interface "ISomeClass", another would like to name it "AbstractSomeClass".
And some guys will name abstract class to "AbstractSomeClass" and interface to "ISomeClass".
What I mean here is, the I means Interface here, and it is not a normal character.
What you want is actually change the grammar to allow other situations than it originally performs, that means a grammar change/rule change of p3c.
and if you want to change the rule, you shall change the rulebook first, then the next step we build the plugin to apply the rule.
you are doing it in a wrong order, guys.
2.
By the way,if you think HBase shall be acceptable, what is your idea about HTTPProtocolHandler?
Shall it be acceptable too?
Or not?
And why?
I mean, HTTPProtocolHandler is actually same as HBase in this question, as:
1.HTTP and Protocol are two words, H and Base are two words.
2.HTTP have a reason to be uppercase, H have a reason to be uppercase.
3.HTTPProtocol is meaningful, HBase is meaningful.

If you think HTTPProtocol is illegal just because it is too long, then what is the exact liminition number would you like?
for example, is FTPProtocol legal? is DPProtocol legal? is HProtocol legal?
I just want you think it deeper.