Revert "Revert "DooMLoRD: use ccache to speed up building between cleanups""

This reverts commit b76e8e253f27b23cd0d7bf8031184d864b887b0b.
Revert "Revert "DooMLoRD: added optimizations for compiling (thanks to @franciscofranco)""

This reverts commit 4443693ce5167d06af04104ab401027ea2a9d696.
Revert "Revert "DooMLoRD: fix for toolchain GCC 4.7 Google""

This reverts commit 1afda2497355f82b4c1855cbe25137068994638e.
Revert "revert: DooMLoRD: shift to XZ compression/decompression"

This reverts commit 37acec40f181b984c99ca152be9db273a9d4e100.