Ignore function call casing, persist parameter %

[MarquessV]

There were two issues to solve here:

1. Ignore casing for function calls

This may be controversial. The Quil spec only ever refers to cis in a lowercase form. I've created this issue for clarification in the spec.

2. Fix parameter output

Parameters for GateDefintion and WaveDefinition are stored in a Vec<String>. These parameters are Quil identifiers prefixed with a % (aka "formal parameters). The parser recognizes these as formal parameters, but stores them on the instruction without the %. This meant they were getting printed back out as Quil without the %, which is incorrect. This fix restores the % on output, though it may make more sense to keep it in the parser. After further discussion we've decided to omit the % as it is a delimiter for quil and doesn't need to be part of the internal representation of a parameter. I've added tests to confirm this approach works for GateDefinition, MeasureCalibrationDefinition and WaveformDefinition.

[Shadow53]

I'm curious about the use of r"" over "" in a couple places, otherwise this looks fine to me.

[kalzoo]

lgtm 👍