FeatureRequest: TextObject Camelcase and underscore

[hmuronaka]

If the text contains '_',

• 'vi_' ... selects the text from the previous '' until the next ''
• 'ci_' ... change the text from the previous, '' until the next ''

If the text doesn't contain '_',

• 'vi_' ... selects the camelcase words
• 'ci_' ... selects the camelcase words

Example select the camelcase words against the text "MyPDFView"

Current cursol	Result vi_
M	My
y	My
P	PDF
D	PDF
F	PDF
V	View
i	View
e	View
w	View

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[alanhamlett]

Related to #379.