BUG-1270: optimize Builders with QName(Module)

Now that we are exposing QNameModule, we can optimize QName
instantiation heavily by passing parent QName and QNameModule instances,
so they will get massively reused.

Change-Id: If67883ea3873a55b563136b743a7453c365475a9
Signed-off-by: Robert Varga <rovarga@cisco.com>
Optimize BindingMapping.toCamelCase()

Instead of replacing characters, we use a CharMatcher in the Splitter.
This elides the need to copy strings and search them multiple times.

Change-Id: Iff0e580f927a5f983a3eb6e2e3b318f33a1b2217
Signed-off-by: Robert Varga <rovarga@cisco.com>