Add multi-AZ and multi-region support

[cartalla]

Add Regions and AZs to the InstanceConfig

The code has been updated support multiple regions.
The instance types that are available and the pricing varies by region so
all instance type info must be maintained by region.

Spot pricing additionally varies by instance type and by AZ and this
commit adds an updated EC2InstanceTypeInfoPkg package that looks up
the spot pricing for each instance type in each AZ and region.

The Region/AZ configuration is added to the InstanceConfig section of the config
file.
The region requires the VpcId, CIDR, and SshKeyPair.
The AZ requires the subnet ID and priority.

The slurm node configuration has been updated to add the AZ id to all compute nodes
and add the AZ name to all partitions.

Users can specify multiple partitions with sbatch if they want jobs to
be spread across multiple AZs.
The modulefile has been updated to set the partition to the list of
all regional/az partitions so that all nodes are available to the jobs
in the priority configured in the config file.

Create compute node security groups for other regions using a custom resource.
Save regional security group ids in ssm parameter store.

Update multi-region route53 hosted zone

Fix IAM permissions to handle multiple regions

Decode iam permissions messsages

Update security groups with remote region cidrs

Create slurmfs ARecord for use in other regions.
This required adding a lambda to do DNS lookups.

Add custom resource to add regional VPCs to the Route53 hosted zone.
This is required for now because of a CDK bug:

aws/aws-cdk#20496

The PR for the above bug is:

aws/aws-cdk#20530

Update github-pages to use mkdocs
Add github-docs target to Makefile

Update to cdk@2.28.1

Create AZ and interactive partitions, set default partitions

Resolves FEATURE #22: Support mutiple availability zones and regions

Issue #, if available:

Description of changes:

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[cartalla]

Add tests that cover all OS distributions and all instance types.

Wait for cluster to be available and then run tests on the clusters to make sure that it worked.