JBIDE-17254: Luna M7

* Updated repos and versions
* Remove feature org.eclipse.equinox.server.p2 (useless and conflicting)
  -> https://bugs.eclipse.org/bugs/show_bug.cgi?id=434870
* Commented out Birt which doesn't have a M7-compatible build
  -> https://issues.jboss.org/browse/JBIDE-17266
JBIDE-17280 update README due to dgolovin's change to remove default TP resolution -- now must explicitly call -Pmultiple2repo
add -Dmirror-target-to-repo.includeSources=true to command that resolves the TP, so sources will be fetched too
JBIDE-17524: Remove ref to jcraft (part of a feature)
Update README.md

Add -Pmultiple2repo into doc
Target Platform 4.40.0.Beta2 release
Move to TP 4.40.0.Beta3-SNAPSHOT
JBIDE-17254, JBIDE-17266, JBIDE-17317, JBIDE-17306: update to latest BIRT, tern.java, and m2e-apt
JBIDE-16757 move m2e.jdt from JBDS TP to Central TP
update README to point at M7, not M6
JBIDE-17254 regenerate IU versions for m2e.apt, birt, and tern
JBIDE-17254 include newer BIRT and version of patched tern site which includes com.googlecode.json-simple 1.1.1, until @VRubezhny can change dep in js.jsdt plugin to use minimal-json instead
JBIDE-17254 should use com.eclipsesource.json 0.9.1 instead of com.googlecode.json-simple 1.1.1
JBIDE-17254 should use com.eclipsesource.json 0.9.1 instead of com.googlecode.json-simple 1.1.1
JBIDE-17254: Use cleaner mirror for tern

Use a mirror that doesn't mix com.eclipsesource.json and minimal-json
Target Platform 4.40.0.Beta3 release
Move to 4.40.0.Beta4-SNAPSHOT
JBIDE-17429 ensure consistent (updated) versions of org.jboss.tools.maven.apt.feature and org.sonatype.m2e.egit.feature across JBT/JBDS/Central target platforms
update README so it's more closely parallel w/ the JBoss Central version; add step4 for producing a p2diff report; if install fails, break
update README so it's more closely parallel w/ the JBoss Central version; add step4 for producing a p2diff report; if install fails, break