Added support for \binom{}{} and \intertext{}

[AndrewReaganM]

Description of the Change

I added support for autocompletion of \binom{}{} and \intertext{} for use within equations.

Alternate Designs

This design was selected due to the absence of support for these common commands.

Benefits

Users will be able to more quickly add binomials and right-justified text to their equations.

Possible Drawbacks

There is a potential for having too many snippets, although binomials are very common.

Applicable Issues

No issues.