descriptor: add decompressible rdata item type
README: simplify instructions for Mac users
Merge branch 'descriptors_compression' into 'master'

See merge request !272
Fixes #289
Reformat NEWS file into reStructuredText
doc: insert supported classes info from KNOWN_ISSUES
doc: add info about supported RR types
tests: log interesting environment variables
semantic checks: convert signer name in RRSIG to lowercase
dnssec: convert signer name to lowercase before validating signatures
remove invalid rcu synchronization
NEWS: typo
Merge branch 'NEWS-in-RST' into 'master'

NEWS in reStructuredText

NEWS file is now in RST format, that should make it easier to parse by automated tools like freshcode.club (http://fossil.include-once.org/freshcode/wiki/Autoupdate)

See merge request !273
zscanner: improve error codes
Merge branch 'dnssec-rrsig-owner-lowercase' into 'master'

DNSSEC: convert signer in RRSIG to lowercase

See merge request !274
zscanner: add test for DOS newline detection
RRSet wire: Unified RDATA-traversing function.

First draft. Requires some optimizations and testing.
Merge branch 'master' into rrset-from-wire
RRSet wire: Fixed bad argument in to_wire()
RRSet wire: rdata_from_wire_one() refactoring

Used traverse_rdata() function. Still needs some polising and
more refactoring (together with the rr_from_wire() function.
RRSet: Fixed from_wire()

Bad source size counting. Still needs polishing.