skins: Make border style of <pre> more subtle for common skins

This changes the border style for skins using skins/common
(Vector and Monobook by default) to be less promiment.

From a dashed dark blue line to a solid line in a lighter shade
of grey.

Bug: 27047
Change-Id: Iea3592508b585c5160cf7f2c2d4c31dd5db43b7a
Batch retreival of ES data with minimal round trips

Batches ES urls by schema and host to reduce round trips required to retreive
many pieces of data.  Takes array of ES urls to retreive and returns a map
from ES urls to their data.  Errored urls are represented with a boolean false
in the result set.  Initially implemented for ExternalStoreDB, other stores
fallback to serial requests.

Change-Id: If1bef25f57bfe7de32fc6787f553a90bd76e87ea
Merge "Batch retreival of ES data with minimal round trips"
Merge "skins: Make border style of <pre> more subtle for common skins"