Adding lman and eval ice modifiers so they don't break syntax highlighting (fixes #5)

[alextorma]

Description

This adds lman and eval as recognized ice modifiers for zinit-vim-syntax

Fixes #5

Motivation and Context

Usage examples

n/a, this simply fixes broken syntax highlighting

How Has This Been Tested?

...by editing my zinit config in vim

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• Bug fix (non-breaking change which fixes an issue)
• Documentation change
• New feature (non-breaking change which adds functionality)

Checklist:

• [ what tests ] All new and existing tests passed.
• [ seriously, what test ] I have added tests to cover my changes.
• [ what documentation? ] I have updated the documentation accordingly.
• I have made changes that should be incorporated into this project that are in line with this project's stated goals.