add info to open cravat variant-info tab

[jmcmichael]

Add the following information to the open-cravat tab:

• CHASMplus

[obigriffith]

Other potential data to pull in through CRAVAT (where available):

• gnomADv3
• ClinVar Significance
• ClinVar Conditions
• Cancer Genome Census
• COSMIC
• CHASMplus
• CADD
• REVEL