abandoned yaml, perl and c key exporters, added json exporter using libjansson, enable with --with-json

tests/unittests.cfg

@@ -267,11 +267,6 @@ temporarily disabled
     expect = /added to/
   </test>
   
-  <test check-vcl-crypto-unencrypted-secret-yaml>
-    cmd = $pcp -V vcl -y
-    expect = /encrypted:  no/
-  </test>
-
   <test check-vcl-prepare-import-bpub>
     cmd = $pcp -V vcl -I key-bobby-pub -K
     expect = /added/
@@ -359,13 +354,6 @@ temporarily disabled
   expect = /Verified/s
 </test>
 
-#
-# yaml export test
-<test check-export-yaml>
-  cmd = $pcp -V va -y | perl -Ilib -MYAML -MData::Dumper -e "print Dumper(Load(join('',<>)))"
-  expect = /VAR1/
-</test>
-
 #
 # raw C test with prepared keys, message and cipher
 <test check-raw-decrypt>