Fix bad interactions between retain points multiplier, as-needed dropping, and variable depth tile pyramids

2.60.0

• Fix bad interaction between --retain-points-multiplier and stopping early when the tile feature limit is reached
• Fix another bad interaction between --retain-points-multiplier, dropping-as-needed, and variable depth tile pyramids
• Add optional BUILD_INFO string to version
• Reorder overzoom logic to clip before dealing with multiplier and filters
• When --generate-variable-depth-tile-pyramid is in use, report the actual highest zoom generated as tileset maxzoom

test-8265594b

Dropping a feature into a multiplier cluster still effectively drops it

test-17c52d0b

Don't try to truncate zooms if we are still tiling at z18

test-fee56eaa

Report the actual max zoom of any tiles as the metadata maxzoom

test-114e7f2a

Update version and changelog

test-c3fa99bc

Be more careful to retry when the feature count is exceeded

test-bc59c6ba

Fix the feature count estimates, I think

test-4bdb8edd

Pass build info into the version string

test-42c4426e

Clip before dealing with multiplier or filters in overzoom

test-459aef11

Try adding --drop-sparsest-as-needed