Add customer_managed_key functionality

[blongv]

Fixes #15 .

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Changes proposed in this pull request

• Add outputs
• Add customer_managed_key optional block.
• Add infrastructure_encryption_enabled variable.
• Add lifecycle ignore_changes tags for environments where tags are enforced by central policies.

@claranet/fr-azure-reviewers